SIRP proteins and uses thereof

ABSTRACT

The present invention features isolated, purified, or enriched nucleic acid encoding a SIRP polypeptide and isolated, purified, or enriched SIRP polypeptide and uses thereof.

FIELD OF THE INVENTION

[0001] This invention relates to receptor tyrosine kinase associated proteins and their uses.

BACKGROUND OF THE INVENTION

[0002] Signal transduction is a fundamental mechanism whereby external stimuli are relayed to the interior of cells. A key aspect of signal transduction involves the reversible phosphorylation of tyrosine residues on proteins. The phosphorylation state of tyrosine residues on a protein is modified through the reciprocal actions of tyrosine kinases (TKs) and tyrosine phosphatases (TPs).

[0003] For example, a variety of polypeptide growth factors and hormones mediate their cellular effects by interacting with cell surface receptors and soluble or cytoplasmic polypeptide containing molecules having tyrosine kinase enzymatic activity (for review, see Williams, et al. Cell 61:203-212 (1990); Carpenter, et al. J. Biol. Chem. 265:7709-7712 (1990)). The interaction of these ligands with their receptors induces a series of events which include receptor dimerization and stimulation of protein tyrosine kinase activity. Tyrosine autophosphorylation on multiple sites creates specific binding sites for target proteins, which bind to the activated receptor with their SH2 domains (for review, see Schlessinger and Ullrich, Neuron 9:383-391, (1992)).

[0004] SH2 (src homology 2) domains are conserved sequences of about 100 amino acids found in cytoplasmic non-receptor tyrosine kinases such as pp60src, PLC-γ, GAP and v-crk (Mayer, et al., Nature 332:272-275 (1988); Pawson, Oncogene 3:491-495 (1988)). While having distinct catalytic domains, all these molecules share conserved SH2 and SH3 (src homology 3) domains and the ability to associate with receptors with tyrosine kinase activity (Anderson, et al. Science 250:979-982 (1990)).

[0005] Tyrosine kinase activation and receptor autophosphorylation are prerequisites for the association between growth factor receptors and SH2 domain-containing proteins (Margolis, et al., Mol. Cell. Biol. 10:435-441- (1990); Kumjian et al., Proc. Natl. Acad. Sci. USA 86:6232-8239 (1989); Kazlauskas, et al., Science 247:1578-1581 (1990)). In particular, the carboxy-terminal (C-terminal) fragment of the epidermal growth factor receptor (EGFR), which contains all the known autophosphorylation sites, binds specifically to the SH2 domains of GAP and PLC-γ (see below). Hence, a major site of association exists between the SH2 domain of these substrate proteins and the tyrosine phosphorylated C-terminal tail of the EGFR.

[0006] Target proteins which bind to activated receptors have been identified by analysis of proteins that co-immunoprecipitate with growth factor receptors, or that bind to receptors attached to-immobilized matrices (Morrison, et al., Cell 58:649-657 (1989); Kazlauskas, et al., EMBO J. 9:3279-3286 (1990)).

[0007] Ohnishi et al. J. Biol. Chem. 271:25569-25574 (1996), not admitted to be prior art, described that a brain specific immunoglobulin-like molecule with tyrosine-based activation motifs, BIT, is associated with protein-tyrosine phosphatase SH-PTP2, whereby two SH2 domains of SH-PTP2 simultaneously interact with two phosphotyrosines of BIT-TAM.

[0008] Phosphotyrosine phosphatases (PTPs) are involved with negative or positive regulation of growth factor-specific cell responses such as mitosis, differentiation, migration, survival, transformation or death. For example, SHP-2 is a phosphotyrosine phosphatase which contains a SH2 domain. SHP-2 is a positive signal transducer for a number of receptor tyrosine kinases (RTKs) and cytokine receptors.

SUMMARY OF THE INVENTION

[0009] Within the scope of this invention, applicant has identified a novel mammalian protein family of at least fifteen members designated SIgnal Regulatory Proteins (SIRPs). In particular, Applicant has cloned and sequenced the coding sequences of 4 members of SIRPs, SIRP1 and SIRP4 from human, and SIRPα1 and SIRPβ1 from mouse. In this regard, the present invention relates to SIRP polypeptides, nucleic acids encoding such polypeptides, cells, tissues and animals containing such polypeptides or nucleic acids, antibodies to such polypeptides or nucleic acids, assays utilizing such polypeptides or nucleic acids, and methods relating to all of the foregoing.

[0010] SIRP family proteins play a general role in the regulation of signals that define diverse physiological and pathological processes. Thus, the present invention provides several agents and methods useful for diagnosing, treating, and preventing various diseases or conditions associated with abnormalities in these pathways as well as assay systems useful for screening for therapeutically effective agents.

[0011] In particular, SIRP polypeptides are involved in various signal transduction pathways such as the negative regulation of signals generated by receptor tyrosine kinases, including, but not limited to, receptors for EGF, insulin and platelet derived growth factor (PDGF). For example, acting like a tumor suppressor, SIRP4 exerts negative regulatory effects on growth factor and hormone induced cellular responses such as DNA synthesis. Oncogenesis may be associated with mutant SIRPs or not enough SIRPs. Restoring SIRPs to their normal levels such as by gene therapy could restore the cells to a normal growth pattern. Insulin receptor activity is also regulated by SIRPS. Overexpression of SIRPs may be involved in type II diabetes where sufficient insulin is present but insulin signaling is deficient. A compound that inhibits the negative regulation of insulin signaling by SIRPs, such as by interfering with the interaction between SIRP and SHP-2 may lead to enhanced insulin signaling.

[0012] All SIRP proteins have a receptor-like, or Immunoglubulin (Ig) like extracellular domain and a transmembrane domain. There are two subtypes of SIRPs distinguished by the presence or absence of a cytoplasmic SHP-2 binding domain. For example, SIRP4 has a cytoplasmic domain while SIRP1 doesn't. The cytoplasmic domain of SIRP4 contains two SHP-2 binding regions each having two tyrosine residues.

[0013] The growth inhibitory effect of SIRP4 depends on phosphorylation of tyrosines and is related to reduced MAP kinase activation. SIRP4 becomes a substrate of activated receptor tyrosine kinases (RTKs) upon EGF, insulin or PDGF stimulation. In its tyrosine phosphorylated form, SIRP4 binds a phosphotyrosine phosphatase, SHP-2, via SH2 interactions. Once SIRP4 binds SHP-2, it activates the catalytic activity of SHP-2 and becomes a substrate of SHP-2. This direct activation of SHP-2 could induce activation of Src or other Src family kinases. The above described interaction allows SIRP4 to participate in major signal transduction pathways involving SHP-2.

[0014] SHP-2 has two SH2 domains and is required for signaling downstream of a variety of RTKs. SHP-2 has been reported to bind directly to RTKs such as PDGF receptor, EGF receptor, and cKit in response to stimulation by their ligands. Insulin receptor substrate 1 (IRS-1) also associates with SHP-2 in response to insulin.

[0015] SIRP4 also binds SHP-1 and Grb2, both of which contain a SH-2 domain. Grb2 is an adapter molecule and one of its functions is to link growth factor receptors to downstream effector proteins. Grb2 is known to bind tyrosine-phosphorylated SHP-2 in response to PDGF stimulation.

[0016] The full length nucleic acid sequences encoding hSIRP1, hSIRP4, mSIRPα1 and mSIRPβ1 proteins are set forth respectively in SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, and SEQ ID NO: 4. The coding regions are nt 41-1237 of SEQ ID NO: 1, nt 13-1524 of SEQ ID NO: 2, nt 59-1597 of SEQ ID NO: 3, and nt 86-1261 of SEQ ID NO: 4.

[0017] The full length amino acid sequences of hSIRP1, hSIRP4, mSIRPα1 and mSIRPβ1 are set forth respectively in SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7, and SEQ ID NO: 8. The first two Ig-like domains of hSIRP1 is from aa 54-227; the third Ig-like domain is from aa 250-330; the extracelluar domain next to the membrane is from aa 336-366; and the transmembrane domain is from aa 367-398. The first two Ig-like domains of hSIRP4 is from aa 1-227; the third Ig-like domain is from aa 250-336; the extracelluar domain next to the membrane, the transmembrane domain, and the cytoplasmic domain immediate next to the membrane are from aa 347-407; and the rest of the cytoplasmic domain is from aa 408-503.

[0018] Thus, in a first aspect the invention features an isolated, purified, enriched or recombinant nucleic acid encoding a SIRP polypeptide. Preferably such nucleic acid encodes a mammalian SIRP polypeptide, more preferably it encodes a human SIRP polypeptide.

[0019] By “isolated” in reference to nucleic acid is meant a polymer of 2 (preferably 21, more preferably 39, most preferably 75) or more nucleotides conjugated to each other, including DNA or RNA that is isolated from a-natural source or that is synthesized. The isolated nucleic acid of the present invention is unique in the sense that it is not found in a pure or separated state in nature. Use of the term “isolated” indicates that a naturally occurring sequence has been removed from its normal cellular environment. Thus, the sequence may be in a cell-free solution or placed in a different cellular environment. The term does not imply that the sequence is the only nucleotide chain present, but does indicate that it is the predominate sequence present (at least 10-20% more than any other nucleotide sequence) and is essentially free (about 90-95% pure at least) of non-nucleotide material naturally associated with it. Therefore, the term does not encompass an isolated chromosome encoding one or more SIRP polypeptides.

[0020] By the use of the term “enriched” in reference to nucleic acid is meant that the specific DNA or RNA sequence constitutes a significantly higher fraction (2-5 fold) of the total DNA or RNA present in the cells or solution of interest than in normal or diseased cells or in the cells from which the sequence was taken. This could be caused by a person by preferential reduction in the amount of other DNA or RNA present, or by a preferential increase in the amount of the specific DNA or RNA sequence, or by a combination of the two. However, it should be noted that enriched does not imply that there are no other DNA or RNA sequences present, just that the relative amount of the sequence of interest has been significantly increased in a useful manner and preferably separate from a sequence library. The term significant here is used to indicate that the level of increase is useful to the person making such an increase, and generally means an increase relative to other nucleic acids of about at least 2 fold, more preferably at least 5 to 10 fold or even more. The term also does not imply that there is no DNA or RNA from other sources. The other source DNA may, for example, comprise DNA from a yeast or bacterial genome, or a cloning vector such as pUC19. This term distinguishes from naturally occurring events, such as viral infection, or tumor type growths, in which the level of one mRNA may be naturally increased relative to other species of mRNA. That is, the term is meant to cover only those situations in which a person has intervened to elevate the proportion of the desired nucleic acid.

[0021] It is also advantageous for some purposes that a nucleotide sequence be in purified form. The term “purified” in reference to nucleic acid does not require absolute purity (such as a homogeneous preparation); instead, it represents an indication that the sequence is relatively purer than in the natural environment (compared to the natural level this level should be at least 2-5 fold greater, e.g., in terms of mg/ml). Individual clones isolated from a cDNA library may be purified to electrophoretic homogeneity. The claimed DNA molecules obtained from these clones could be obtained directly from total DNA or from total RNA. The cDNA clones are not naturally occurring, but rather are preferably obtained via manipulation of a partially purified naturally occurring substance (messenger RNA). The construction of a cDNA library from mRNA involves the creation of a synthetic substance (cDNA) and pure individual cDNA clones can be isolated from the synthetic library by clonal selection of the cells carrying the cDNA library. Thus, the process which includes the construction of a cDNA library from mRNA and isolation of distinct cDNA clones yields an approximately 10⁶-fold purification of the native message. Thus, purification of at least one order of magnitude, preferably two or three orders, and more preferably four or five orders of magnitude is expressly contemplated.

[0022] By “SIRP polypeptide” is meant 9 or more contiguous amino acids set forth in the full length amino acid sequence of SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7, or SEQ ID NO: 8. The SIRP polypeptides can be encoded by full-length nucleic acid sequences or any portion of a full-length nucleic acid sequence, so long as a functional activity of the polypeptide is retained. Preferred functional activities include the ability to bind to a receptor tyrosine kinase or a SH-2 domain bearing protein such as SHP-2, SHP-1 or Grb-2. A non full-length SIRP polypeptide may be used to elicit an antibody against the polypeptide and the full-length polypeptide using techniques known to those skilled in the art. The present invention also encompasses deletion mutants lacking one or more isolated SIRP domains (e.g., Ig-like domain, transmembrane domain, SH2 binding domain, and tyrosine residues), and complementary sequences capable of hybridizing to full length SIRP protein under stringent hybridization conditions.

[0023] In preferred embodiments, isolated nucleic acid comprises, consists essentially of, or consists of a nucleic acid sequence set forth in the full length nucleic acid sequence SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, or SEQ ID NO: 4 or at least 27, 30, 45, 60 or 90 contiguous nucleotides thereof and the SIRP polypeptide comprises, consists essentially of, or consists of at least 9, 10, 15, 20, 30, 50, 100, 200, or 300 contiguous amino acids of a SIRP polypeptide.

[0024] By “comprising” it is meant including, but not limited to, whatever follows the word “comprising”. Thus, use of the term “comprising” indicates that the listed elements are required or mandatory, but that other elements are optional and may or may not be present. By “consisting of” is meant including, and limited to, whatever follows the phrase “consisting of”. Thus, the phrase “consisting of” indicates that the listed elements are required or mandatory, and that no other elements may be present. By “consisting essentially of” is meant including any elements listed after the phrase, and limited to other elements that do not interfere with or contribute to the activity or action specified in the disclosure for the listed elements. Thus, the phrase “consisting essentially of” indicates that the listed elements are required or mandatory, but that other elements are optional and may or may not be present depending upon whether or not they affect the activity or action of the listed elements.

[0025] Compositions and probes of the present invention may contain human nucleic acids encoding a SIRP polypeptide but are substantially free of nucleic acid not encoding SIRP polypeptide. The human nucleic acid encoding a SIRP polypeptide is at least 18 contiguous bases of the nucleotide sequence set forth in SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, or SEQ ID NO: 4 and will selectively hybridize to human genomic DNA encoding a SIRP polypeptide, or is complementary to such a sequence. The nucleic acid may be isolated from a natural source by cDNA cloning or subtractive hybridization; the natural source may be blood, semen, and tissue of various organisms including eukaryotes, mammals, birds, fish, plants, gorillas, rhesus monkeys, chimpanzees and humans; and the nucleic acid may be synthesized by the triester method or by using an automated DNA synthesizer. In yet other preferred embodiments the nucleic acid is a conserved or unique region, for example those useful for the design of hybridization probes to facilitate identification and cloning of additional polypeptides, the design of PCR probes to facilitate cloning of additional polypeptides, and obtaining antibodies to polypeptide regions.

[0026] By “conserved nucleic acid regions”, are meant regions present on two or more nucleic acids encoding a SIRP polypeptide, to which a particular nucleic acid sequence can hybridize to under lower stringency conditions. Examples of lower stringency conditions suitable for screening for nucleic acid encoding SIRP polypeptides are provided in Abe, et al. J. Biol. Chem., 19:13361 (1992) (hereby incorporated by reference herein in its entirety, including any drawings). Preferably, conserved regions differ by no more than 7 out of 20 nucleotides.

[0027] By “unique nucleic acid region” is meant a sequence present in a full length nucleic acid coding for a SIRP polypeptide that is not present in a sequence coding for any other naturally occurring polypeptide. Such regions preferably comprise 12 or 20 contiguous nucleotides present in the full length nucleic acid encoding a SIRP polypeptide.

[0028] The invention also features a nucleic acid probe for the detection of a nucleic acid encoding a SIRP polypeptide in a sample. The nucleic acid probe contains nucleic acid that will hybridize to at least one sequence set forth in SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, or SEQ ID NO: 4.

[0029] In preferred embodiments the nucleic acid probe hybridizes to nucleic acid encoding at least 12, 27, 30, 35, 40, 50, 100, 200, or 300 contiguous amino acids of the full-length sequence set forth in SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7, or SEQ ID NO: 8. Various low or high stringency hybridization conditions may be used depending upon the specificity and selectivity desired.

[0030] By “high stringency hybridization conditions” is meant those hybridizing conditions that (1) employ low ionic strength and high temperature for washing, for example, 0.015 M NaCl/0.0015 M sodium citrate/0.1% SDS at 50° C.; (2) employ during hybridization a denaturing agent such as formamide, for example, 50% (vol/vol) formamide with 0.1% bovine serum albumin/0.1% Ficoll/0.1% polyvinylpyrrolidone/50 mM sodium phosphate buffer at pH 6.5 with 750 mM NaCl, 75 mM sodium citrate at 42° C.; or (3) employ 50% formamide, 5×SSC (0.75 M NaCl, 0.075 M Sodium pyrophosphate, 5×Denhardt's solution, sonicated salmon sperm DNA (50 g/ml), 0.1% SDS, and 10% dextran sulfate at 42° C., with washes at 42° C. in 0.2×SSC and 0.1% SDS. Under stringent hybridization conditions only highly complementary nucleic acid sequences hybridize. Preferably, such conditions prevent hybridization of nucleic acids having 1 or 2 mismatches out of 20 contiguous nucleotides.

[0031] Methods for using the probes include detecting the presence or amount of SIRP RNA in a sample by contacting the sample with a nucleic acid probe under conditions such that hybridization occurs and detecting the presence or amount of the probe bound to SIRP RNA. The nucleic acid duplex formed between the probe and a nucleic acid sequence coding for a SIRP polypeptide may be used in the identification of the sequence of the nucleic acid detected (for example see, Nelson et al., in Nonisotopic DNA Probe Techniques, p. 275 Academic Press, San Diego (Kricka, ed., 1992) hereby incorporated by reference herein in its entirety, including any drawings). Kits for performing such methods may be constructed to include a container means having disposed therein a nucleic acid probe.

[0032] The invention also features recombinant nucleic acid, preferably in a cell or an organism. The recombinant nucleic acid may contain a sequence (coding sequence or noncoding sequence) or a segment of sequence set forth in SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, or SEQ ID NO: 4 and a vector or a promoter effective to initiate transcription in a host cell. The recombinant nucleic acid can alternatively contain a transcriptional initiation region functional in a cell, a sequence complimentary to an RNA sequence encoding a SIRP polypeptide and a transcriptional termination region functional in a cell.

[0033] In another aspect the invention features an isolated, enriched or purified SIRP polypeptide.

[0034] By “isolated” in reference to a polypeptide is meant a polymer of 2 (preferably 7, more preferably 13, most preferably 25) or more amino acids conjugated to each other, including polypeptides that are isolated from a natural source or that are synthesized. The isolated polypeptides of the present invention are unique in the sense that they are not found in a pure or separated state in nature. Use of the term “isolated” indicates that a naturally occurring sequence has been removed from its normal cellular environment. Thus, the sequence may be in a cell-free solution or placed in a different cellular environment. The term does not imply that the sequence is the only amino acid chain present, but that it is the predominate sequence present (at least 10-20% more than any other sequence) and is essentially free (about 90-95% pure at least) of non-amino acid material naturally associated with it.

[0035] By the use of the term “enriched” in reference to a polypeptide is meant that the specific amino acid sequence constitutes a significantly higher fraction (2-5 fold) of the total of amino acids present in the cells or solution of interest than in normal or diseased cells or in the cells from which the sequence was taken. This could be caused by a person by preferential reduction in the amount of other amino acids present, or by a preferential increase in the amount of the specific amino acid sequence of interest, or by a combination of the two. However, it should be noted that enriched does not imply that there are no other amino acid sequences present, just that the relative amount of the sequence of interest has been significantly increased. The term significant here is used to indicate that the level of increase is useful to the person making such an increase, and generally means an increase relative to other amino acids of about at least 2 fold, more preferably at least 5 to 10 fold or even more. The term also does not imply that there is no amino acid from other sources. The other source amino acid may, for example, comprise amino acid encoded by a yeast or bacterial genome, or a cloning vector such as pUC19. The term is meant to cover only those situations in which man has intervened to elevate the proportion of the desired amino acid.

[0036] It is also advantageous for some purposes that an amino acid sequence be in purified form. The term “purified” in reference to a polypeptide does not require absolute purity (such as a homogeneous preparation); instead, it represents an indication that the sequence is relatively purer than in the natural environment (compared to the natural level this level should be at least 2-5 fold greater, e.g., in terms of mg/ml). Purification of at least one order of magnitude, preferably two or three orders, and more preferably four or five orders of magnitude is expressly contemplated. The substance is preferably free of contamination at a functionally significant level, for example 90%, 95%, or 99% pure.

[0037] In preferred embodiments SIRP polypeptides contain at least 9, 10, 15, 20, or 30 contiguous amino acids of the full-length sequence set forth in SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7, or SEQ ID NO: 8.

[0038] In yet another aspect the invention features a purified antibody (e.g., a monoclonal or polyclonal antibody) having specific binding affinity to a SIRP polypeptide. The antibody contains a sequence of amino acids that is able to specifically bind to a SIRP polypeptide.

[0039] By “specific binding affinity” is meant that the antibody will bind to a hSIRP polypeptide at a certain detectable amount but will not bind other polypeptides to the same extent, under identical conditions. The present invention also encompasses antibodies that can distinguish hSIRP1 from hSIRP2 or hSIRP3 or can otherwise distinguish between the various SIRPs.

[0040] Antibodies having specific binding affinity to a SIRP polypeptide may be used in methods for detecting the presence and/or amount of a SIRP polypeptide is a sample by contacting the sample with the antibody under conditions such that an immunocomplex forms and detecting the presence and/or amount of the antibody conjugated to the SIRP polypeptide. Diagnostic kits for performing such methods may be constructed to include a first container means containing the antibody and a second container means having a conjugate of a binding partner of the antibody and a label.

[0041] In another aspect the invention features a hybridoma which produces an antibody having specific binding affinity to a SIRP polypeptide.

[0042] By “hybridoma” is meant an immortalized cell line which is capable of secreting an antibody, for example a SIRP antibody.

[0043] In preferred embodiments the SIRP antibody comprises a sequence of amino acids that is able to specifically bind a SIRP polypeptide.

[0044] Another aspect of the invention features a method of detecting the presence or amount of a compound capable of binding to a SIRP polypeptide. The method involves incubating the compound with a SIRP polypeptide and detecting the presence or amount of the compound bound to the SIRP polypeptide.

[0045] In preferred embodiments, the compound inhibits an activity of SIRP. The present invention also features compounds capable of binding and inhibiting SIRP polypeptide that are identified by methods described above.

[0046] In another aspect the invention features a method of screening potential agents useful for treatment of a disease or condition characterized by an abnormality in a signal transduction pathway that contains an interaction between a SIRP polypeptide and a natural binding partner (NBP). The method involves assaying potential agents for those able to promote or disrupt the interaction as an indication of a useful agent.

[0047] By “NBP” is meant a natural binding partner of a SIRP polypeptide that naturally associates with a SIRP polypeptide. The structure (primary, secondary, or tertiary) of the particular natural binding partner will influence the particular type of interaction between the SIRP polypeptide and the natural binding partner. For example, if the natural binding partner comprises a sequence of amino acids complementary to the SIRP polypeptide, covalent bonding may be a possible interaction. Similarly, other structural characteristics may allow for other corresponding interactions. The interaction is not limited to particular residues and specifically may involve phosphotyrosine, phosphoserine, or phosphothreonine residues. A broad range of sequences may be capable of interacting with SIRP polypeptides. One example of a natural binding partner may be SHP-2, which is described above. Other examples include, but are not limited to, SHP-1 and Grb2. Using techniques well known in the art, one may identify several natural binding partners for SIRP polypeptides such as by utilizing a two-hybrid screen.

[0048] By “screening” is meant investigating an organism for the presence or absence of a property. The process may include measuring or detecting various properties, including the level of signal transduction and the level of interaction between a SIRP polypeptide and a NBP.

[0049] By “disease or condition” is meant a state in an organism, e.g., a human, which is recognized as abnormal by members of the medical community. The disease or condition may be characterized by an abnormality in one or more signal transduction pathways in a cell wherein one of the components of the signal transduction pathway is either a SIRP polypeptide or a NBP. Specific diseases or disorders which might be treated or prevented, based upon the affected cells include cancers and diabetes.

[0050] In preferred embodiments, the methods described herein involve identifying a patient in need of treatment. Those skilled in the art will recognize that various techniques may be used to identify such patients.

[0051] By “abnormality” is meant an a level which is statistically different from the level observed in organisms not suffering from such A disease or condition and may be characterized as either an excess amount, intensity or duration of signal or a deficient amount, intensity or duration of signal. The abnormality in signal transduction may be realized as an abnormality in cell function, viability or differentiation state. The present invention is based in part on the determination that such abnormality in a pathway can be alleviated by action at the SHP-2-SIRP interaction site in the pathway. An abnormal interaction level may also either be greater or less than the normal level and may impair the normal performance or function of the organism. Thus, it is also possible to screen for agents that will be useful for treating a disease or condition, characterized by an abnormality in the signal transduction pathway, by testing compounds for their ability to affect the interaction between a SIRP polypeptide and SHP-2, since the complex formed by such interaction is part of the signal transduction pathway. However, the disease or condition may be characterized by an abnormality in the signal transduction pathway even if the level of interaction between the SIRP polypeptide and NBP is normal.

[0052] By “interact” is meant any physical association between polypeptides, whether covalent or non-covalent. This linkage can include many chemical mechanisms, for instance covalent binding, affinity binding, intercalation, coordinate binding and complexation. Examples of non-covalent bonds include electrostatic bonds, hydrogen bonds, and Van der Waals bonds. Furthermore, the interactions between polypeptides may either be direct or indirect. Thus, the association between two given polypeptides may be achieved with an intermediary agent, or several such agents, that connects the two proteins of interest (e.g., a SIRP polypeptide and SHP-2). Another example of an indirect interaction is the independent production, stimulation, or inhibition of both a SIRP polypeptide and SHP-2 by a regulatory agent. Depending upon the type of interaction present, various methods may be used to measure the level of interaction. For example, the strengths of covalent bonds are often measured in terms of the energy required to break a certain number of bonds (i.e., kcal/mol) Non-covalent interactions are often described as above, and also in terms of the distance between the interacting molecules. Indirect interactions may be described in a number of ways, including the number of intermediary agents involved, or the degree of control exercised over the SIRP polypeptide relative to the control exercised over SHP-2 or another NBP.

[0053] By “disrupt” is meant that the interaction between the SIRP polypeptide and SHP-2 or a NBP is reduced either by preventing expression of the SIRP polypeptide, or by preventing expression of SHP-2 or NBP, or by specifically preventing interaction of the naturally synthesized proteins or by interfering with the interaction of the proteins.

[0054] By “promote” is meant that the interaction between a SIRP polypeptide and SHP-2 or NBP is increased either by increasing expression of a SIRP polypeptide, or by increasing expression of SHP-2 or a NBP, or by decreasing the dephosphorylating activity of the corresponding regulatory PTP (or other phosphatase acting on other phosphorylated signaling components) by promoting interaction of the SIRP polypeptide and SHP-2 or NBP or by prolonging the duration of the interaction. Covalent binding can be promoted either by direct condensation of existing side chains or by the incorporation of external bridging molecules. Many bivalent or polyvalent linking agents are useful in coupling polypeptides, such as an antibody, to other molecules. For example, representative coupling agents can include organic compounds such as thioesters, carbodiimides, succinimide esters, diisocyanates, glutaraldehydes, diazobenzenes and hexamethylene diamines. This listing is not intended to be exhaustive of the various classes of coupling agents known in the art but, rather, is exemplary of the more common coupling agents. (See Killen and Lindstrom 1984, J. Immunol. 133:1335-2549; Jansen, F. K., et al., 1982, Immunological Rev. 62:185-216; and Vitetta et al., supra).

[0055] By “signal transduction pathway” is meant the sequence of events that involves the transmission of a message from an extracellular protein to the cytoplasm through a cell membrane. The signal ultimately will cause the cell to perform a particular function, for example, to uncontrollably proliferate and therefore cause cancer. Various mechanisms for the signal transduction pathway (Fry et al., Protein Science., 2:1785-1797, 1993) provide possible methods for measuring the amount or intensity of a given signal. Depending upon the particular disease associated with the abnormality in a signal transduction pathway, various symptoms may be detected. Those skilled in the art recognize those symptoms that are associated with the various other diseases described herein. Furthermore, since some adapter molecules recruit secondary signal transducer proteins towards the membrane, one measure of signal transduction is the concentration and localization of various proteins and complexes. In addition, conformational changes that are involved in the transmission of a signal may be observed using circular dichroism and fluorescence studies.

[0056] In another aspect the invention features a method of diagnosis of an organism for a disease or condition characterized by an abnormality in a signal transduction pathway that contains an interaction between a SIRP polypeptide and SHP-2 or a NBP. The method involves detecting the level of interaction as an indication of said disease or condition.

[0057] By “organism” is meant any living creature. The term includes mammals, and specifically humans. Preferred organisms include mice, as the ability to treat or diagnose mice is often predictive of the ability to function in other organisms such as humans.

[0058] By “diagnosis” is meant any method of identifying a symptom normally associated with a given disease or condition. Thus, an initial diagnosis may be conclusively established as correct by the use of additional confirmatory evidence such as the presence of other symptoms. Current classification of various diseases and conditions is constantly changing as more is learned about the mechanisms causing the diseases or conditions. Thus, the detection of an important symptom, such as the detection of an abnormal level of interaction between SIRP polypeptides and SHP-2 or NBPs may form the basis to define and diagnose a newly named disease or condition. For example, conventional cancers are classified according to the presence of a particular set of symptoms. However, a subset of these symptoms may both be associated with an abnormality in a particular signaling pathway, such as the ras²¹ pathway and in the future these diseases may be reclassified as ras²¹ pathway diseases regardless of the particular symptoms observed.

[0059] Yet another aspect of the invention features a method for treatment of an organism having a disease or condition characterized by an abnormality in a signal transduction pathway. The signal transduction pathway contains an interaction between a SIRP polypeptide and SHP-2 or a NBP and the method involves promoting or disrupting the interaction, including methods that target the SIRP:NBP interaction directly, as well as methods that target other points along the pathway.

[0060] By “dominant negative mutant protein” is meant a mutant protein that interferes with the normal signal transduction pathway. The dominant negative mutant protein contains the domain of interest (e.g., an SIRP polypeptide or SHP-2 or a NBP), but has a mutation preventing proper signaling, for example by preventing binding of a second domain from the same protein. One example of a dominant negative protein is described in Millauer et al., Nature Feb. 10, 1994. The agent is preferably a peptide which blocks or promotes interaction of the SIRP polypeptide and SHP-2 or another NBP. The peptide may be recombinant, purified, or placed in a pharmaceutically acceptable carrier or diluent.

[0061] An EC₅₀ or IC₅₀ of less than or equal to 100 μM is preferable, and even more preferably less than or equal to 50 μM, and most preferably less that or equal to 20 μM. Such lower EC₅₀'s or IC₅₀'s are advantageous since they allow lower concentrations of molecules to be used in vivo or in vitro for therapy or diagnosis. The discovery of molecules with such low EC₅₀'s and IC₅₀'s enables the design and synthesis of additional molecules having similar potency and effectiveness. In addition, the molecule may have an EC₅₀ or IC₅₀ less than or equal to 100 μM at one or more, but not all cells chosen from the group consisting of parathyroid cell, bone osteoclast, juxtaglomerular kidney cell, proximal tubule kidney cell, distal tubule kidney cell, cell of the thick ascending limb of Henle's loop and/or collecting duct, central nervous system cell, keratinocyte in the epidermis, parafollicular cell in the thyroid (C-cell), intestinal cell, trophoblast in the placenta, platelet, vascular smooth muscle cell, cardiac atrial cell, gastrin-secreting cell, glucagon-secreting cell, kidney mesangial cell, mammary cell, beta cell, fat/adipose cell, immune cell and GI tract cell.

[0062] By “therapeutically effective amount” is meant an amount of a pharmaceutical composition having a therapeutically relevant effect. A therapeutically relevant effect relieves to some extent one or more symptoms of the disease or condition in the patient; or returns to normal either partially or completely one or more physiological or biochemical parameters associated with or causative of the disease or condition. Generally, a therapeutically effective amount is between about 1 nmole and 1 μmole of the molecule, depending on its EC₅₀ or IC₅₀ and on the age and size of the patient, and the disease associated with the patient.

[0063] In another aspect, the invention describes a polypeptide comprising a recombinant SIRP polypeptide or a unique fragment thereof. By “unique fragment,” is meant an amino acid sequence present in a full-length SIRP polypeptide that is not present in any other naturally occurring polypeptide. Preferably, such a sequence comprises 6 contiguous amino acids present in the full sequence. More preferably, such a sequence comprises 12 contiguous amino acids present in the full sequence. Even more preferably, such a sequence comprises 18 contiguous amino acids present in the full sequence.

[0064] By “recombinant SIRP polypeptide” is meant to include a polypeptide produced by recombinant DNA techniques such that it is distinct from a naturally occurring polypeptide either in its location (e.g., present in a different cell or tissue than found in nature), purity or structure. Generally, such a recombinant polypeptide will be present in a cell in an amount different from that normally observed in nature.

[0065] In another aspect, the invention describes a recombinant cell or tissue containing a purified nucleic acid coding for a SIRP polypeptide. In such cells, the nucleic acid may be under the control of its genomic regulatory elements, or may be under the control of exogenous regulatory elements including an exogenous promoter. By “exogenous” it is meant a promoter that is not normally coupled in vivo transcriptionally to the coding sequence for the SIRP polypeptide.

[0066] In another aspect, the invention features a SIRP polypeptide binding agent able to bind to a SIRP polypeptide. The binding agent is preferably a purified antibody which recognizes an epitope present on a SIRP polypeptide. Other binding agents include molecules which bind to the SIRP polypeptide and analogous molecules which bind to a SIRP polypeptide.

[0067] By “purified” in reference to an antibody is meant that the antibody is distinct from naturally occurring antibody, such as in a purified form. Preferably, the antibody is provided as a homogeneous preparation by standard techniques. Uses of antibodies to the cloned polypeptide include those to be used as therapeutics, or as diagnostic tools.

[0068] In another aspect, the invention provides a nucleic acid molecule comprising a nucleotide sequence that encodes a polypeptide having the full length amino acid sequence set forth in SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7, or SEQ ID NO: 8 except that it lacks at least one of the domains selected from the group consisting of the extracellular Ig like domain, the transmembrane domain, and the SHP-2 binding domains. Such deletion mutants are useful in the design of assays for protein inhibitors. The nucleic acid molecules described above may be, for example, cDNA or genomic DNA and may be placed in a recombinant vector or expression vector. In such a vector, the nucleic acid preferably is operatively associated with the regulatory nucleotide sequence containing transcriptional and translational regulatory information that controls expression of the nucleotide sequence in a host cell.

[0069] Thus, the invention also provides a genetically engineered host cell containing any of the nucleotide sequences described herein and the nucleic acid preferably is operatively associated with the regulatory nucleotide sequence containing transcriptional and translational regulatory information that controls expression of the nucleotide sequence in a host cell. Such host cells may obviously be either prokaryotic or eukaryotic.

[0070] Other features and advantages of the invention will be apparent from the following description of the preferred embodiments thereof, and from the claims.

BRIEF DESCRIPTION OF THE FIGURES

[0071]FIG. 1 shows the deduced amino acid sequences of SIRP4 and SIRP1. Identical amino acids are boxed. The putative signal sequence and transmembrane region are indicated by thin and thick overlines, respectively. Three Ig-like domains are indicated by stippled overlines. Potential tyrosine phosphorylation sites are shown in bold, the C-terminal proline rich region is shaded. The location of oligonucleotides flanking the Ex region is indicated by stars.

[0072]FIG. 2 shows the alignment of extracellular regions including the first Ig-like domain of 15 SIRP family members. Ex1 shows amino acids encoded by the initial PCR fragment that was used for screening and GST-fusion protein construction. Ex2-11 are derived from PCR and cDNA sequences, Ex12-15 from genomic isolates. Numbering is according to FIG. 1.

[0073]FIG. 3 shows the alignment of amino acid sequences of human SIRP4, mouse SIRP1, human SIRPα1 and mouse SIRPβ1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0074] The present invention relates to SIRP polypeptides, nucleic acids encoding such polypeptides, cells, tissues and animals containing such nucleic acids, antibodies to such polypeptides, assays utilizing such polypeptides, and methods relating to all of the foregoing. Those skilled in the art will recognize that many of the methods described below in relation to SIRP1, SIRP4, SHP-2, SHP-1 and Grb2 could also be utilized with respect to the other members of this group.

[0075] Various other features and aspects of the invention are: Nucleic Acid Encoding A SIRP Polypeptide; A Nucleic Acid Probe for the Detection of SIRP; Probe Based Method And Kit For Detecting SIRP; DNA Constructs Comprising a SIRP Nucleic Acid Molecule and Cells Containing These Constructs; Purified SIRP Polypeptides; SIRP Antibody And Hybridoma; An Antibody Based Method And Kit For Detecting SIRP; Isolation of Compounds Which Interact With SIRP; Compositions; Disruption of Protein Complexes; Antibodies to Complexes; Pharmaceutical Formulations and Modes of Administration; Identification of Agents; Purification and Production of Complexes; Derivatives of Complexes; and Evaluation of Disorders.

[0076] All of these aspects and features are explained in detail with respect to another protein involved with signal transduction, PYK-2, in PCT publication WO 96/18738, which is incorporated herein by reference in its entirety, including any drawings. Those skilled in the art will readily appreciate that such description can be easily adapted to SIRP as well, and is equally applicable to the present invention.

EXAMPLES

[0077] The examples below are non-limiting and are merely representative of various aspects and features of the procedures used to identify the full-length nucleic acid and amino acid sequences of a series of SIRP proteins. Experiments demonstrating SIRP expression, interaction and signaling activities are also provided.

[0078] Material and Methods

[0079] Cell Culture and Transient Expression

[0080] MM5/C1, Rat1-IR, A431 or human fibroblast cells were grown until confluency, starved for 18 hours in serum-free medium, and either left untreated or were POV—(1 mM sodium orthovanadate, 3 mM H₂O₂), insulin—(100 nM), EGF—(1 nM), or PDGF—(100 pM) stimulated for different time intervals as indicated. SIRP4, SHP-2 (Vogel, et al., Science 259:1611-1614 (1994)) or SHP-2C463A mutant (Stein-Gerlach, et al. J. Biol. Chem. 270:24635-24637 (1995)) cDNAs were transiently cotransfected in BHK-IR, BHK-EGFR or BHK-βPDGFR cells using the calcium precipitation method (Chen, et al. Mol. Cell. Biol. 7:2745-2752 (1987)). After stimulation, cells were lysed in buffer containing 50 mM HEPES, pH 7.5, 150 mM NaCl, 1% Triton X-100, 10% glycerol, 1 mM POV, 1 mM EDTA, 1 mM PMSF, 1 mg/ml leupeptin, 1 mg/ml aprotinin.

[0081] Immunoprecipitation and Western Blotting

[0082] SHP-2 immunoprecipitations were performed with polyclonal anti-SHP-2 antibodies (Vogel, et al., Science 259:1611-1614 (1994)). Overexpressed SIRP4 or endogenous SIRP4-like proteins were immunoprecipitated by polyclonal anti-Ex1 antibodies raised by immunizing rabbits with a GST-fusion protein containing the Ex1 fragment (FIG. 2). Western blots were labeled with monoclonal anti-phosphotyrosine antibodies 5E2 (Fendly, et al., Cancer Res. 50:1550-1558 (1990)), and after stripping, reprobed with monoclonal anti-SHP-2 antibodies (Transduction Laboratories), or polyclonal anti-SIRP4-CT antibodies, raised against a GST-fusion protein containing the C-terminal part of SIRP4 (amino acids 336-503). For immunolabeling goat anti-mouse or -rabbit horseradish peroxidase conjugates (Bio-Rad) and the ECL detection system (Amersham) were used.

[0083] To obtain 293 cells stably expressing SIRP4 (293/SIRP4), cells were transfected with SIRP4 cDNA in pLXSN (Miller, et al. Biotechniques 7:980-988 (1989)) using the calcium precipitation method, followed by selection with G418 (1 mg/ml). SIRP4 was immunoprecipitated from quiescent or POV-stimulated (1 mM) 293/SIRP4 cells with polyclonal anti-Ex1 antibodies. Subsequently, crude lysates of [³⁵S]-methionine labeled 293 cells expressing different SH2 domain containing proteins were added to the affinity matrix and incubated for 2 h at 4° C. The is immunocomplexes were washed, separated by SDS-PAGE and analyzed by autoradiography.

[0084] Enzymatic Deglycosylation

[0085] To perform in vitro deglycosylation SHP-2 immunocomplexes or the 110 kDa protein preparation were first denatured in the presence of 1% SDS at 100° C. for 5 min. Deglycosylation was done in potassium phosphate buffer (40 mM, pH 7.0), containing 20 mM EDTA, 1% b-mercaptoethanol, 1% Triton X-100 and 0.5 Unit of Endoglycosidase F/N-Glycosidase F (Boehringer Mannheim) at 37° C. for 16 hours.

[0086] Protein Purification

[0087] Approximately 10¹⁰ Rat1-IR cells were used to purify the 110 kDa protein. Starved Rat1-IR cells were insulin-stimulated (100 nM) for 10 min, washed briefly with ice-cold hypotonic buffer containing 20 mM HEPES, pH 7.5, 1 mM POV, 1 mM EDTA, 1 mM PMSF, 1 mg/ml leupeptin, 1 mg/ml aprotinin, scraped into the same buffer and homogenized. Obtained cell extracts were pelleted at 1000 rpm for 15 min, and supernatants were spun at 48.000 g for 1 hour. Membranes were solubilized in lysis buffer as described above. hIR was depleted from membrane extracts using an affinity column with monoclonal anti-hIR antibody 83-14 (Redemann et al., Mol. Cell. Biol. 12:491-498 (1992)), covalently coupled to Protein A-Sepharose beads (Pharmacia). Depleted extracts were applied onto a WGA-agarose 6 MB column (Sigma), and glycoproteins were eluted with 0.3 M N-acetyl-glucosamine in HNTG (20 mM HEPES (pH 7.5), 150 mM NaCl, 0.1% Triton X-100, 10% glycerol, 1 mM POV). After concentration protein extracts were applied onto an anti-phosphotyrosine antibody column (Sigma). Bound proteins were eluted with 20 mM phosphotyrosine in HNTG. The eluate was subjected to SDS-PAGE, proteins were transferred to a PVDF membrane (Millipore) and stained with Coomassie blue. The protein of 110 kD apparent molecular weight was microsequenced. The following five tryptic peptides were obtained: PIYSFIGGEHFPR, IVEPDTEIK, YGFSPR, IKEVAHVNLEVR, VAAGDSAT.

[0088] Biological Assays

[0089] To produce retroviruses expressing pLXSN, wild type SIRP4 and mutated SIRP4 constructs, BOSC 23 cells were transiently transfected by expression plasmids as described (Pear, et al. Proc. Natl. Acad. Sci. 90:8392-8396 (1993)). To obtain NIH3T3 cells stably expressing wild type SIRP4, SIRP4-4Y or SIRP4-DCT mutants subconfluent NIH3T3 cells (10⁵ cells per 6 cm dish) were incubated with supernatants of transfected BOSC 23 cells for 4 h in the presence of Polybrene (4 mg/ml), followed by selection with G418 (1 mg/ml).

[0090] To perform focus formation assays cell lines 3T3/pLXSN, 3T3/SIRP4, 3T3/SIRP4-4Y or 3T3/SIRP4-DCT were superinfected for 4 hours with equal volumes of v-fms-virus supernatant (10⁵cells/6 cm dish). Cells were cultivated for 14 days in 4% FCS with medium change every second day. Cell foci were stained with Crystal violet (0.1% crystal violet, 30% methanol).

Example 1 Identification and Cloning of Signal Regulatory Proteins

[0091] Western blot of mammalian cells with anti-phosphotyrosine antibodies and anti-SHP-2 antibodies was used to identify tyrosine phosphorylated SHP-2 associated proteins.

[0092] Western blots containing anti-SHP-2 immunoprecipitates from starved or POV-treated mouse MM5/C1 mammary carcinoma, rat fibroblast Rat1-IR or human epidermal carcinoma A431 cells were incubated with anti-phosphotyrosine antibodies or anti-SHP-2 antibodies. Samples were deglycosylated with or treated without Endoglycosidase F/N-Glycosidase F (Endo.F/F). As a control, insulin-stimulated Rat1-IR cell lysates were immunoprecipitated with preimmune rabbit serum (aNS).

[0093] Samples from each purification step (i.e., solubilized crude membrane extract, hIR-depleted extracts, concentrated eluate from WGA-agarose beads, and eluate from anti-phosphotyrosine antibody column) were analyzed by 10% SDS-PAGE and visualized by silver staining and in Western blots using monoclonal anti-phosphotyrosine antibodies.

[0094] A major tyrosine phosphorylated protein was revealed in analysis of anti-SHP-2 immunoprecipitates from both pervanadate (POV) and growth factor stimulated cells. This phosphoprotein migrated at 120 kDa, 110 kDa and 90 kDa positions in mouse mammary tumor (MM5/C1) cells, Rat1 cells overexpressing the human insulin receptor (Rat1-IR), and human epidermoid carcinoma (A431) cells, respectively.

[0095] Upon in vitro deglycosylation, this glycoprotein was reduced to 65 kDa apparent molecular weight (MW) in all cases. This indicated that the same SHP-2 binding protein of 65 kDa was differentially glycosylated in a species specific manner.

[0096] In some cell lines such as A431, other tyrosine phosphorylated proteins in the 90-120 kDa range remained unaffected by the deglycosylation treatment. These proteins may represent Gab1 and/or the human homologue of the Drosophila DOS protein.

[0097] Insulin treated Rat1-IR were used to purify the 110 kDa SHP-2 binding glycoprotein using standard chromatography procedures. Approximately 4 mg of the glycoprotein that copurified with SHP-2 were obtained and subject to microsequence analysis. This yielded five peptide sequences: PIYSFIGGEHFPR, IVEPDTEIK, YGFSPR, IKEVAHVNLEVR, VAAGDSAT. Computer aided search in the EST database led to the identification of a 305 bp rat sequence (accession Nr.: H31804) and subsequent human cDNA fragment of 2 kb (EMBL databank, accession Nr.: U6701) containing matching and homologous sequences, respectively.

[0098] Specific primers flanking the very 5′ portion of this sequence were used to amplify a 360 bp human DNA fragment (encoding Ex1 in FIG. 2) which was used to screen a human placenta cDNA library.

[0099] Several positive clones were isolated. One clone of 2.4 kb encoded a polypeptide of 503 amino acids designated SIRP4 (for SIgnal Regulating Protein 4) with a calculated mass of 57,000. The deduced sequence identifies SIRP4 as a transmembrane protein with three Ig-like domains and a cytoplasmic portion containing four potential tyrosine phosphorylation sites and one proline-rich region.

[0100] A second cDNA clone, SIRP1, is also identified. This protein is highly homologous to SIRP4 within the Ig-like domains (Ig-1: 83%; Ig-2: 88%; Ig-3: 83%), but displays striking sequence divergence at the amino terminus and upstream of the transmembrane domain which gives rise to a shorter protein that still contains a transmembrane-like region but lacks the cytoplasmic C-terminal portion.

[0101] SIRP4 and SIRP1 are members of a novel protein family. This protein family has a variety of distinct sequence isoforms as evidenced by comparison of fifteen cDNA and genomic sequences within the first Ig-like domain (FIG. 2). Two major classes exist in SIRP family distinguished by the presence or absence of a cytoplasmic SHP-2 binding domain.

Example 2 Analyzing the Functions of SIRP4

[0102] SIRP4 Binds to SHP-2 and Serves as a Substrate for SHP-2, IR, EGFR, and βPDGFR

[0103] The identity of SIRP4 as SHP-2 binding protein and substrate was confirmed by expression of the SIRP4 cDNA either alone or in combination with SHP-2 or an enzymatically inactive mutant SHP-2C463A in BHK cells. BHK cells stably express human EGF-, insulin- or βPDGF receptors.

[0104] Immunoprecipitations were performed with a polyclonal antibody raised against a GST-fusion protein containing the extracellular Ex1 region (FIG. 2).

[0105] Western blots containing anti-SIRP4 immunoprecipitations from quiescent or ligand-stimulated BHK-IR, BHK-EGFR or BHK-βPDGF cells were labeled with anti-phosphotyrosine, anti-SHP-2 and anti-SIRP4 antibodies, respectively.

[0106] Anti-SIRP4 immunoprecipitation revealed a tyrosine phosphorylated protein of 85-90 kDa upon ligand stimulation which associated with SHP-2.

[0107] The results suggested SIRP4 to be a direct substrate of SHP-2 since expression of the SHP-2 mutant SHP-2C463A led to a significant increase in its phosphotyrosine content (even in starved cells) while coexpression of wt SHP-2 resulted in dephosphorylation. The MW of overexpressed SIRP4 matches that of the endogenous protein detected in SHP-2 immunoprecipitates from A431 cells.

[0108] Endogenous SIRP4-like proteins were immunoprecipitated from untreated or EGF-stimulated A431 cells, from quiescent or PDGF-treated human fibroblasts, or from starved or insulin-stimulated HBL-100 cells. As a control, ligand-stimulated cell lysates were immunoprecipitated with preimmune rabbit serum (aNS). Immunoblots were probed with monoclonal anti-phosphotyrosine and monoclonal anti-SHP-2 antibodies.

[0109] Polyclonal anti-Ex1 antibodies immunoprecipitate a protein of 85-90 kDa apparent MW from A431, HBL-100 tumor cells and human fibroblasts. This protein was tyrosine phosphorylated upon EGF, insulin or PDGF stimulation, respectively, and coprecipitated with SHP-2 in a ligand dependent manner.

[0110] These data indicate the existence of SIRP4 in several human cell lines where SIRP4 serves as a substrate for insulin-, EGF- and βPDGF receptors, binds SHP-2 in its tyrosine phosphorylated form and serves as a substrate for the phosphatase activity of SHP-2. The interaction of SHP-2 with SIRP4 likely involves one or both SH2 domains of SHP-2 as suggested by the requirement of phosphotyrosine residues and the abrogation of detectable association by mutation of critical residues in SHP-2 SH2 domains.

[0111] In vitro binding assays were performed to determine whether SIRP4 is able to interact with other SH2 domain-containing proteins. SIRP4-associated [³⁵S]-Methionine labeled proteins were resolved on SDS-PAGE and detected by autoradiography. The result shows that SIRP4 associates with both SHP-1 and Grb2 but not p85, Shc, Grb7, PLC-g, c-src, Nck, Vav, GAP, or ISGF-3.

[0112] A catalytically inactive SHP-1 mutant has recently been shown to bind an as yet unidentified tyrosine phosphorylated protein of 90-95-kDa in human 293 cells. This tyrosine phosphorylated protein is likely to be SIRP4 or one of its family members.

[0113] Effects of SIRP4 on Cell Growth and Transformation

[0114] To investigate the biological function of SIRP4, three stable transfectants of NIH3T3 cells were constructed to express wild type SIRP4 or SIRP4 mutants carrying either point mutations of the putative SHP-2 tyrosine binding sites (SIRP4-4Y) or a deletion of most of the cytoplasmic region (SIRP4-DCT).

[0115] Ligand-stimulated [³H]-thymidine incorporation of NIH3T3 cells expressing empty vector (3T3/pLXSN), wild type SIRP4 (3T3/SIRP4), SIRP4-4Y (3T3/SIRP4-4Y) or SIRP4-DCT (3T3/SIRP4-DCT, amino acids 402-503 are deleted) mutants. Cells were grown to confluence in 24-well dishes (Nunc), starved for 24 h in DMEM/0.5% FCS, stimulated with different concentrations of insulin or EGF for 18 h, then incubated with 0.5 mCi [³H]-thymidine per well for 4 h. Incorporation into DNA was determined as described (Redemann, et al. Mol. Cell. Biol. 12:491-498 (1992)).

[0116] Upon stimulation of cells with insulin, EGF and PDGF, control cells showed growth factor-induced DNA synthesis as measured by [³H]-thymidine incorporation. Overexpression of SIRP4 led to a decrease of [³H]-thymidine incorporation. In contrast, both SIRP4 mutants had nearly no effect on DNA synthesis. The observed inhibitory effect on DNA synthesis must be connected to SIRP4 tyrosine phosphorylation and/or its association with SHP-2 since wt SIRP4 became tyrosine phosphorylated and bound to SHP-2 upon ligand stimulation, and SIRP4 mutants did not.

[0117] SIRP4 effected growth inhibition upon insulin or EGF stimulation is correlated with reduced MAP kinase activation in 3T3/SIRP4 cells. 3T3/pLXSN, 3T3/SIRP4 or 3T3/SIRP4-4Y cells were starved for 18 hours in DMEM/0.5% FCS and stimulated with insulin or EGF for the time indicated. MAP kinase was detected in Western blots by using polyclonal erk1 and erk2 antibodies (Santa Cruz). In contrast, expression of SIRP4 mutants defective in SHP-2 binding had no effect on MAP kinase activation. Similar observations were made upon stimulation of the cells with PDGF.

[0118] These data strongly indicate that SIRP4 represents a novel regulatory-element in the pathway that leads to MAP kinase activation.

[0119] We next determined the consequence of SIRP4 overexpression on oncogene mediated transformation of NIH3T3 cells. To examine the ability of SIRP4 to influence the formation of cell foci, subconfluent 3T3/pLXSN, 3T3/SIRP4, 3T3/SIRP4-4Y or 3T3/SIRP4-DCT cells were infected with v-fms virus supernatants. As measured by focus formation, transformation by a v-fms retrovirus was significantly suppressed in cells overexpressing wt SIRP4 but not in cells expressing mutant SIRP4.

[0120] Previous reports have described certain SHP-2 binding proteins of 110-130 kDa apparent MW in mouse, rat or hamster cells. Tyrosine hyperphosphorylation of these proteins was observed when an enzymatically inactive SHP-2 mutant was overexpressed. In addition, disruption of SHP-2 function induced a variety of negative effects on growth factor-induced cellular signals. Our experiments strongly indicate that these proteins belong to the SIRP family and that the biological effects previously observed are due to the function of these SIRP proteins.

[0121] Without being bound by any theory, applicant proposes that tyrosine docking sites on SIRP proteins for either SHP-2 and/or other SH2 proteins such as SHP-1 or Grb2 play a significant role since the inhibitory effect of SIRP4 on NIH3T3 cell proliferation and transformation depends on phosphorylation of tyrosines.

[0122] One or both of the SHP phosphatases may tightly regulate the SIRP4 phosphorylation state.

[0123] SIRP4 may also act in its phosphorylated state as a “trapping” protein that sequesters SHP-2 from activated RTKs. The sequestion makes SHP-2 unavailable for other positive regulatory functions such as an adapter which recruits the Grb2-SOS complex to activated receptors. Such a function is supported by the observation that SHP-2 has higher affinity to the tyrosine phosphorylated form of SIRP4 than to autophosphorylated insulin and EGF receptors (Yamauchi, et al., J. Biol. Chem. 270:17716-17722, Yamauchi, et al. J. Biol. Chem. 270:14871-14874 (1995)).

[0124] A third possibility is based on the membrane-spanning structural features of the SIRP4 variant. The high degree of sequence diversity within the Ig-domains is reminiscent of immunoglobulin variable regions and suggests a role of extracellular determinants in the SIRP related signal transduction. Structurally defined interaction of SIRP with specific receptors, soluble ligands, extracellular matrix components or other factors may result in specific regulatory consequences for intracellular signaling events.

[0125] All publications referenced are incorporated by reference herein, including the nucleotide sequences, amino acid sequences, drawings and tables in each publication. All the compounds disclosed and referred to in the publications mentioned above are incorporated by reference herein, including those compounds disclosed and referred to in articles cited by the publications mentioned above.

[0126] Other embodiments of this invention are disclosed in the following claims. As will be obvious to those skilled in the art, may variations and modifications may be made without departing from the spirit and scope of the invention.

1 26 1 3804 DNA Homo sapiens 1 cacagacgtt tggacagagc aggctcctaa ggtctccaga atgcccgtgc cagcctcctg 60 gccccacctt cctagtcctt tcctgctgat gacgctactg ctggggagac tcacaggagt 120 ggcaggtgag gacgagctac aggtgattca gcctgaaaag tccgtatcag ttgcagctgg 180 agagtcggcc actctgcgct gtgctatgac gtccctgatc cctgtggggc ccatcatgtg 240 gtttagagga gctggagcag gccgggaatt aatctacaat cagaaagaag gccacttccc 300 acgggtaaca actgtttcag aactcacaaa gagaaacaac ctgaactttt ccatcagcat 360 cagtaacatc accccagcag acgccggcac ctactactgt gtgaagttcc ggaaagggag 420 ccctgacgac gtggagttta agtctggagc aggcactgag ctgtctgtgc gcgccaaacc 480 ctctgccccc gtggtatcgg gccctgcggt gagggccaca cctgagcaca cagtgagctt 540 cacctgcgag tcccatggct tctctcccag agacatcacc ctgaaatggt tcaaaaatgg 600 gaatgagctc tcagacttcc agaccaacgt ggaccccgca ggagacagtg tgtcctacag 660 catccacagc acagccaggg tggtgctgac ccgtggggac gttcactctc aagtcatctg 720 cgagatggcc cacatcacct tgcaggggga ccctcttcgt gggactgcca acttgtctga 780 ggccatccga gttccaccca ccttggaggt tactcaacag cccatgaggg cagagaacca 840 ggcaaacgtc acctgccagg tgagcaattt ctacccccgg ggactacagc tgacctggtt 900 ggagaatgga aatgtgtccc ggacagaaac agcttcgacc ctcatagaga acaaggatgg 960 cacctacaac tggatgagct ggctcctggt gaacacctgt gcccacaggg acgatgtggt 1020 gctcacctgt caggtggagc atgatgggca gcaagcagtc agcaaaagct atgccctgga 1080 gatctcagca caccagaagg agcacggctc agatatcacc catgaaccag cgctggctcc 1140 tactgctcca ctcctcgtag ctctcctcct gggccccaag ctgctactgg tggttggtgt 1200 ctctgccatc tacatctgct ggaaacagaa ggcctgactg accctcagtc tctgctgcct 1260 cctcctttct tgagaagctc agcctgagag aaggagctgg cgagaacctt ccccacactc 1320 agctccaaac gcctcctctc ccaggtcatc tgcctgccca cacgctcctg ttccaccttc 1380 acaagaccat gatgccccaa agcagtgtct ctattcacgg tcctgagcag gggccatggg 1440 attgggctct gggcactgac tcatggcacc tccctagaag gtgagaaaca ctccaaatct 1500 aaacacacca ggacttctcc catccgtcgc cttgggactg gccataaacc acagactctc 1560 tccaggctct caagagttat cctgtcttct ggattcctgc ctaccccaac tcccccagcc 1620 ttgttgaggt tctctactgc ctcctgaata cacatgaacc cctataccaa ttttaagaaa 1680 aaaatgattc tctttcctct ttgtccaagc atcctatccc tcaaacccaa aaagaaagaa 1740 gctctccctt ctctctctgt gatggagaca gtatttcttc tagtatcctg cagccttccc 1800 agtcctgctg cttgtggtag aaattgctgc cacagcccaa cattgaggag ccctcgatga 1860 ctgcccttta caactcatat tcagttctgc ctccaaaatg catgtgtcca cttacatgag 1920 atggtaaatg tttaacaatg gactttctga aagggaaaaa ccaaaagctg ttttgcagtg 1980 cttgccaatt tctctagtgt aataactccc aacctgacca atttcagcac tgccaacagt 2040 taaacaacca gattcgaaga ttcctgaaat ttaacaattg gttttcaggg cccagtccaa 2100 gcctgctgct ggaaacctca gagttaaatc cctattctcc acacctctca cctccaccac 2160 ccctccctgt cccagccagc atcatctctt tggggaccac tcctctggct ttcatttttc 2220 agccacagtg attctttgga aaagtcaaat catatcactt ctctgcttct tccccaacac 2280 agctgcatgg tcccgctctc cctccttcaa gtctctgctc aatgtcactt cattaaaggc 2340 ggccttctat aaactacctt gtataaaata ttatttattt tctctatccc ggcattctaa 2400 tttctcttat cctaattaat ttttctttag cccttatttt gatgagtatt atgccgaata 2460 caggcagccc tcacttttca tggccagtgc aagattgcaa aaagactgtg caacctgaaa 2520 cccaggaaag cagtctccat agtcaatcag aaaaacaatg atcattctgt gacctttacc 2580 attttttgtc aaaatattag aaactctcac actctcagtt acaaatgtag aggacaatga 2640 aaatataatg aaataaatat ttatttgtgc actacaattc aaagcattag aaacattgaa 2700 gtcaatggcg tttcttgtaa atgtatccag atgaggttgg aagagtgctt gacctttttg 2760 tatatttcta atatggagtg atatagtttg gctctgtgtc tccatccaaa tctcatctta 2820 aattgtaatc tgcatgtgtt gtgggaatgg gacctaggta ggaggtgact gaatacatgg 2880 gggcggactt cccccttgct gttcttgtga tagtgagttc tcataagatc tcagtgagtt 2940 ctcatgagat ctggtttttt gaaagtgtgt ggcaagtccc ccttcgctct ctctctctct 3000 ctccctcctg ccaccatgtg aagaaggtgc ctgcttcctt ttctccttcc accatggttg 3060 taagtttcct gaggcctccc agtcatgctt cctgttaagc ctgtggaact gtgagtccaa 3120 ttaaacctct tttattcata aaatatccag tttctggtag ttctttatag cagtgtgaga 3180 atgggctaat acacggagca agcatcgttc tttcattttt atttatttta ttttttgaga 3240 tggagtttca ccttattccc aggctggagt gcaatgtcgt gatcttggct cactgcaacc 3300 cccgcctcca gggttcaagt gattctcctg cctcagcctc ctgagtagct gggattacag 3360 gcatgtacca ccacacccag ctaattttgt atttttagta gagatggggt ttctccatgt 3420 tgatcagact agtcttgaac tcccgacctc aggtgatcca cctgtcttgg cctcccaaag 3480 tgctgggatt acaggcatga gccaccatgc ctagccagca agcatcattt ctattatacc 3540 ttggtgtttg cctctttcta agtttggact agcttccaac atcttatccc ttgaattttc 3600 aatattgtgg aatcactcca gaagatcctt tcatgtgaag ttttttgctg gcatttcaac 3660 ctttgggaca tcttcagccc ttttattacc actcctctcc catttgtggc agtttgcgtt 3720 tactacctcc ctctggctgc ctatctgaag ttcctgcatc agggtctaca ttgccacagt 3780 caactatttg tacttctaga attc 3804 2 2433 DNA Homo sapiens 2 cagccgcggc ccatggagcc cgccggcccg gcccccggcc gcctcgggcc gctgctctgc 60 ctgctgctcg ccgcgtcctg cgcctggtca ggagtggcgg gtgaggagga gctgcaggtg 120 attcagcctg acaagtccgt atcagttgca gctggagagt cggccattct gcactgcact 180 gtgacctccc tgatccctgt ggggcccatc cagtggttca gaggagctgg accagcccgg 240 gaattaatct acaatcaaaa agaaggccac ttcccccggg taacaactgt ttcagagtcc 300 acaaagagag aaaacatgga cttttccatc agcatcagta acatcacccc agcagatgcc 360 ggcacctact actgtgtgaa gttccggaaa gggagccctg acacggagtt taagtctgga 420 gcaggcactg agctgtctgt gcgtgccaaa ccctctgccc ccgtggtatc gggccctgcg 480 gcgagggcca cacctcagca cacagtgagc ttcacctgcg agtcccacgg cttctcaccc 540 agagacatca ccctgaaatg gttcaaaaat gggaatgagc tctcagactt ccagaccaac 600 gtggaccccg taggagagag cgtgtcctac agcatccaca gcacagccaa ggtggtgctg 660 acccgcgagg acgttcactc tcaagtcatc tgcgaggtgg cccacgtcac cttgcagggg 720 gaccctcttc gtgggactgc caacttgtct gagaccatcc gagttccacc caccttggag 780 gttactcaac agcccgtgag ggcagagaac caggtgaatg tcacctgcca ggtgaggaag 840 ttctaccccc agagactaca gctgacctgg ttggagaatg gaaacgtgtc ccggacagaa 900 acggcctcaa ccgttacaga gaacaaggat ggtacctaca actggatgag ctggctcctg 960 gtgaatgtat ctgcccacag ggatgatgtg aagctcacct gccaggtgga gcatgacggg 1020 cagccagcgg tcagcaaaag ccatgacctg aaggtctcag cccacccgaa ggagcagggc 1080 tcaaataccg ccgctgagaa cactggatct aatgaacgga acatctatat tgtggtgggt 1140 gtggtgtgca ccttgctggt ggccctactg atggcggccc tctacctcgt ccgaatcaga 1200 cagaagaaag cccagggctc cacttcttct acaaggttgc atgagcccga gaagaatgcc 1260 agagaaataa cacaggacac aaatgatatc acatatgcag acctgaacct gcccaagggg 1320 aagaagcctg ctccccaggc tgcggagccc aacaaccaca cggagtatgc cagcattcag 1380 accagcccgc agcccgcgtc ggaggacacc ctcacctatg ctgacctgga catggtccac 1440 ctcaaccgga cccccaagca gccggccccc aagcctgagc cgtccttctc agagtacgcc 1500 agcgtccagg tcccgaggaa gtgaatggga ccgtggtttg ctctagcacc catctctacg 1560 cgctttcttg tcccacaggg agccgccgtg atgagcacag ccaacccagt tcccggaggg 1620 ctggggcggt gcaggctctg ggacccaggg gccagggtgg ctcttctctc cccacccctc 1680 cttggctctc cagcacttcc tgggcagcca cggccccctc ccccaacatt gccacacacc 1740 tggaggctga cgttgccaaa ccagccaggg aaccaacctg ggaagtggcc agaactgcct 1800 ggggtccaag aactcttgtg cctccgtcca tcaccatgtg ggttttgaag accctcgact 1860 gcctccccga tgctccgaag cctgatcttc cagggtgggg aggagaaaat cccacctccc 1920 ctgacctcca ccacctccac caccaccacc accaccacca ccaccactac caccaccacc 1980 caactggggc tagagtgggg aagatttccc ctttagatca aactgcccct tccatggaaa 2040 agctggaaaa aaactctgga acccatatcc aggcttggtg aggttgctgc caacagtcct 2100 ggcctccccc atccctaggc aaagagccat gagtcctgga ggaggagagg acccctccca 2160 aaggactgga agcaaaaccc tctgcttcct tgggtccctc caagactccc tggggcccaa 2220 ctgtgttgct ccacccggac ccatctctcc cttctagacc tgagcttgcc cctccagcta 2280 gcactaagca acatctcgct gtaagcgcct gtaaattact gtgaaatgtg aaacgtgcaa 2340 tcttgaaact gaggtgttag aaaacttgat ctgtggtgtt ttgttttgtt ttttttctta 2400 aaacaacagc aacgtgaaaa aaaaaaaaaa aaa 2433 3 3645 DNA Mus sp. 3 gcccgcctgc cgagcgcgct caccgccgct ctccctcctt gctctgcagc cgcggcccat 60 ggagcccgcc ggcgcccctg gccgcctagg gccgctgctg ctctgcctgc tgctctccgc 120 gtcctgtttc tgtacaggag tcacggggaa agaactgaag gtgactcagc ctgagaaatc 180 agtgtctgtt gctgctgggg attcgaccgt tctgaactgc actttgacct ccttgttgcc 240 ggtgggaccc attaagtggt acagaggagt aggcaaagcc ggctgtttga tctacagttt 300 cacaggagaa cactttcctc gagttacaaa tgtttcagat gctactaaga gaaacaatat 360 ggacttttcc atccgtatca gtaatgtcac cccagaagat gccggtacct actactgtgt 420 gaagttccag aaaggaccat cagagcctga cacagaaata caatctggag ggggaacaga 480 ggtctatgta ctcgccaaac cttctccacc ggaggatccc cccaggagac aggggcatac 540 tgaccagaaa gtgaacttca cctgcaagtc tcatggcttc tctccccgga atatcaccct 600 gaagtggttc aaagatgggc aagaactcca ccccttggag accaccgtga accctagtgg 660 aaagaatgtc tcctacaaca tctccagcac agtcagggtg gtactaaact ccatggatgt 720 tcattctaag gtcatctgcg aggtagccca catcaccttg gatagaagcc ctcttcgtgg 780 gattgctaac ctgtctaact tcatccgagt ttcacccacc gtgaaggtca cccaacagtc 840 cccgacgtca atgaaccagg tgaacctcac ctgccgggat gagaggttct accccgagga 900 tctccagctg atctggctgg agaatggaaa cgtatcacgg aatgacacgc ccaagaatct 960 cacaaagaac acggatggga cctataatta cacaagcttg ttcctggtga actcatctgc 1020 tcatagagag gacgtggtgt tcacgtgcca ggtgaagcac gaccaacagc cagcgatcac 1080 ccgaaaccat accgtgctgg gacttgccca ctcgagtgat caagggagca tgcaaacctt 1140 ccctggtaat aatgctaccc acaactggaa tgtcttcatc ggtgtgggcg tggcgtgtgc 1200 tttgctcgta gtcctgctga tggctgctct ctacctcctc cggatcaaac agaagaaagc 1260 caaggggtca acatcttcca cacggttgca cgagcccgag aagaacgcca gggaaataac 1320 ccaggtacag tctttgatcc aggacacaaa tgacatcaac gacatcacat acgcagacct 1380 gaatctccca aagagaagga agcccgcacc cggctccctt gagttcctta acaaccacac 1440 agaatatgca agcattgaga caggcaaagt gcctaggcca gaggataccc tcacctatgc 1500 tgacctggac atggtccacc tcagccgggc acagccagcc cccaagcctg agccatcttt 1560 ctcagagtat gctagtgtcc aggtccagag gaagtgaatg gggctgtggt ctgtactagg 1620 ccccatcccc acaagttttc ttgtcctaca tggagtggcc atgacgagga catccagcca 1680 gccaatcctg tccccagaag gccaggtggc acgggtccta ggaccagggg taagggtggc 1740 ctttgtcttc cctccgtggc tcttcaacac ctcttgggca ccacgtcccc ttcttccgga 1800 ggctgggtct tgcagaacca gagggcgaac tggagaaatc tgcctggaat ccaagaagtg 1860 ttgtgcctcg gcccatcact cgtgggctcg gatcctggtc ttggcaaccc caggttgcgt 1920 ccttgatgtt ccagagcttg gtcttctgtg tggagaagag ctcaccatct ctacccaact 1980 tgagctttgg gaccagactc cctttagatc aaaccgcccc atctgtggaa gaactacacc 2040 agaagtcgac aagttttcag ccaacagtgt ctggcctccc cacctcccag gctgactagc 2100 ctggggagaa ggaaccctct cctcctagac cagcagagac tccctgggca tgttcagtgt 2160 ggccccacct cccttccagt cccagcttgc ttcctccagc tagcactaac tcagcagcat 2220 cgctctgtgg acgcctgtaa attattgaga aatgtgaact gtgcagtctt aaagctaagg 2280 tgttagaaaa tttgatttat gctgtttagt tgttgttggg tttcttttct ttttaatttc 2340 tttttctttt ttgatttttt ttctttccct taaaacaaca gcagccagca tcttggctct 2400 ttgtcatgtg ttgaatggtt gggtcttgtg aagtctgagg tctaacagtt tattgtcctg 2460 gaaggatttt cttacagcag aaacagattt ttttcaaatt cccagaatcc tgaggaccaa 2520 gaaggatccc tcagctgcta cttccagcac gcagcgtcac tgggacgaac caggccctgt 2580 tcttacaagg ccacatggcg ggcctttgcc tccatggcta ctgtggtaag tgcagccttg 2640 tctgacccaa tgctgaccta atgttggcca ttccacattg aggggacaag gtcagtgatg 2700 ccccccttgg ctcacaagca cttcagaggc atgcagagag aagggacact cgtccagctc 2760 tctgaggtaa tcagtgcaag gaggagtccg ttttttgcca gcaaacctca gcaggatcac 2820 actggaacag aacctggtca tacctgtgac aacacagctg tgagccaggg caaaccaccc 2880 actgtcactg gctcgagagt ctgggagagc tctgacccga caccctttaa actggatgcc 2940 ggggcctggc tgggcaatgc caagtggtta tggcaaccct gactatctgg tcttaacatg 3000 tagctcagga agtggaggcg ctaatgtccc caatccctgg ggattcctga ttccagctat 3060 tcatgtaagc agagccaacc tgcctatttc tgtagggtgc gactgggatg ttaggagcac 3120 agcaaggacc cagctctgta gggctggtga cctgatacct tctcataatg gcatctagaa 3180 gttaggctga gttgcctcac tggcccagca aaccagaact tgtctttggc cgggccatgt 3240 tcttgggctg tcttctaatt ccaaagggtt ggttggtaaa gctccacccc cttctcctct 3300 gcctaaagac ataacatgtg tatacacaca cgggtgtata gatgagttaa aagaatgtcc 3360 tcgctggcat cctaattttg tcttaagttt ttttggaggg agaaaggaac aaggcaaggg 3420 aagatgtgta gctttggctt taaccaggca gcctgggggc tcccaagcct atggaaccct 3480 ggtacaaaga agagaacaga agcgccctgt gaggagtggg atttgttttt ctgtagacca 3540 gatgagaagg aaacaggccc tgttttgtac atagttgcaa cttaaaattt ttggcttgca 3600 aaatattttt gtaataaaga tttctgggta acaataaaaa aaaaa 3645 4 2020 DNA Mus sp. 4 ccctcactaa agggaacaaa agctggagct ccaccgcggt ggcggccgct ctagaactag 60 tggatccccc gggctgcagg caaccatgct tctcctagat gcctggaccc acattcctca 120 ctgtgtcctg ctgttgatcc tgcttctggg acttaaagga gcagctatga gagagctgaa 180 ggtgatccaa cctgttaaat cattttttgt tggtgctgga gggtcagcca ctctgaactg 240 cacagtgaca tctctcctcc ctgtggggcc catgaggtgg tacaggggta taggacaaag 300 tcgactcttg atatactcgt tcacaggaga aggcttcccc agaataacaa atacttcaga 360 tactacaaag agaaacaaca tggacttttc catccgtatc agtaatgtca ctcctgctga 420 ttcgggtacc tactactgtg tgaagttcca gagaggacca tcagactttt acactgagat 480 tcagtctgga ggtggcactg agttgtcagt acttgctaaa ccatcttcac ctatggtctc 540 cggtcctgca gccagagctg tccctcagca gacagtgacc tttacatgca gatcccatgg 600 attctttccg cggaacctca cgctgaagtg gttcaagaat ggagatgaga tctctcactt 660 ggaaacttct gtggaaccgg aagaaacaag tgtctcctat agagtttcca gcacagtcca 720 ggtggtgttg gaacctaggg atgtccgctc tcagatcatc tgtgaagtgg atcatgtcac 780 tttagatcga gcccctctca gagggattgc tcacatctct gagttcattc aagttccacc 840 caccctggag atccgccagc agccaacaat ggtttggaat gtgataaatg ttacctgcca 900 aatacagaag ttctatcctc caagttttca gttgacctgg ttagagaatg gaaatatatc 960 ccggagagaa gtacctttta cacttacagt aaacaaggat ggaacttaca actggatcag 1020 ctgtctcttg gtgaacatat ctgcccttga ggagaacatg gtagtgacat gccaggttga 1080 gcatgatgga caagcagaag tcattgaaac ccatactgtg gtggtcactg aacatcagag 1140 agtgaaaggt actgctacca agtctggtga ggtcttcacc ccacccttat gtctaaatgt 1200 aaattgggct ttatttttta tgtataaggt aacattcttg attattgtag cattatcctg 1260 acaactacaa agtaaaatgt taacgtcata tttcattccc aacttctcac acgtctcaca 1320 tatctttcca ctaatagatt aaatagttaa gaatggaagg tatcatcaaa ttccagtatc 1380 ttgccccttc cctgttttac ctaacatttg tgaacatcct tatgctcatg tgtttccttt 1440 accatatctt tactgactcc attacatttt agatatttcc taaatatagt gtcctaatgg 1500 agtgaaattt caacgggtca cctgacaacc tgtttgtaca cacacacaca cacacacaca 1560 cacacacaca cacacagcat atgatctgga ctaatgaaat aaaggaaaat caaatgtcca 1620 ttggagcact gctatcacta aggtataagg aaaacttgct agcaaagtat ttcttttcaa 1680 cttgttacga tgctagcagt tagtttgcat tagattggac ccatttatgt gaatatcttt 1740 ttccttctct taaaacaaca aaaaagatcc tcaactccag tgacttttga aaaactcatg 1800 ttccttggca tccctccttt gctgtgagtt cattggctgg ataaacactg ggtcgcctaa 1860 ttatctataa atatgccagt taaaaatgtc aaggttagaa agcatcagtc catacagtgc 1920 aaatatagtc cacagtgggt gctcaggtaa atcatgatat tttcatttaa aatatacatt 1980 caataaaatt aactgtagtt caaaaaaaaa aaaaaaaaaa 2020 5 398 PRT Homo sapiens 5 Met Pro Val Pro Ala Ser Trp Pro His Leu Pro Ser Pro Phe Leu Leu 1 5 10 15 Met Thr Leu Leu Leu Gly Arg Leu Thr Gly Val Ala Gly Glu Asp Glu 20 25 30 Leu Gln Val Ile Gln Pro Glu Lys Ser Val Ser Val Ala Ala Gly Glu 35 40 45 Ser Ala Thr Leu Arg Cys Ala Met Thr Ser Leu Ile Pro Val Gly Pro 50 55 60 Ile Met Trp Phe Arg Gly Ala Gly Ala Gly Arg Glu Leu Ile Tyr Asn 65 70 75 80 Gln Lys Glu Gly His Phe Pro Arg Val Thr Thr Val Ser Glu Leu Thr 85 90 95 Lys Arg Asn Asn Leu Asn Phe Ser Ile Ser Ile Ser Asn Ile Thr Pro 100 105 110 Ala Asp Ala Gly Thr Tyr Tyr Cys Val Lys Phe Arg Lys Gly Ser Pro 115 120 125 Asp Asp Val Glu Phe Lys Ser Gly Ala Gly Thr Glu Leu Ser Val Arg 130 135 140 Ala Lys Pro Ser Ala Pro Val Val Ser Gly Pro Ala Val Arg Ala Thr 145 150 155 160 Pro Glu His Thr Val Ser Phe Thr Cys Glu Ser His Gly Phe Ser Pro 165 170 175 Arg Asp Ile Thr Leu Lys Trp Phe Lys Asn Gly Asn Glu Leu Ser Asp 180 185 190 Phe Gln Thr Asn Val Asp Pro Ala Gly Asp Ser Val Ser Tyr Ser Ile 195 200 205 His Ser Thr Ala Arg Val Val Leu Thr Arg Gly Asp Val His Ser Gln 210 215 220 Val Ile Cys Glu Met Ala His Ile Thr Leu Gln Gly Asp Pro Leu Arg 225 230 235 240 Gly Thr Ala Asn Leu Ser Glu Ala Ile Arg Val Pro Pro Thr Leu Glu 245 250 255 Val Thr Gln Gln Pro Met Arg Ala Glu Asn Gln Ala Asn Val Thr Cys 260 265 270 Gln Val Ser Asn Phe Tyr Pro Arg Gly Leu Gln Leu Thr Trp Leu Glu 275 280 285 Asn Gly Asn Val Ser Arg Thr Glu Thr Ala Ser Thr Leu Ile Glu Asn 290 295 300 Lys Asp Gly Thr Tyr Asn Trp Met Ser Trp Leu Leu Val Asn Thr Cys 305 310 315 320 Ala His Arg Asp Asp Val Val Leu Thr Cys Gln Val Glu His Asp Gly 325 330 335 Gln Gln Ala Val Ser Lys Ser Tyr Ala Leu Glu Ile Ser Ala His Gln 340 345 350 Lys Glu His Gly Ser Asp Ile Thr His Glu Pro Ala Leu Ala Pro Thr 355 360 365 Ala Pro Leu Leu Val Ala Leu Leu Leu Gly Pro Lys Leu Leu Leu Val 370 375 380 Val Gly Val Ser Ala Ile Tyr Ile Cys Trp Lys Gln Lys Ala 385 390 395 6 503 PRT Homo sapiens 6 Met Glu Pro Ala Gly Pro Ala Pro Gly Arg Leu Gly Pro Leu Leu Cys 1 5 10 15 Leu Leu Leu Ala Ala Ser Cys Ala Trp Ser Gly Val Ala Gly Glu Glu 20 25 30 Glu Leu Gln Val Ile Gln Pro Asp Lys Ser Val Ser Val Ala Ala Gly 35 40 45 Glu Ser Ala Ile Leu His Cys Thr Val Thr Ser Leu Ile Pro Val Gly 50 55 60 Pro Ile Gln Trp Phe Arg Gly Ala Gly Pro Ala Arg Glu Leu Ile Tyr 65 70 75 80 Asn Gln Lys Glu Gly His Phe Pro Arg Val Thr Thr Val Ser Glu Ser 85 90 95 Thr Lys Arg Glu Asn Met Asp Phe Ser Ile Ser Ile Ser Asn Ile Thr 100 105 110 Pro Ala Asp Ala Gly Thr Tyr Tyr Cys Val Lys Phe Arg Lys Gly Ser 115 120 125 Pro Asp Thr Glu Phe Lys Ser Gly Ala Gly Thr Glu Leu Ser Val Arg 130 135 140 Ala Lys Pro Ser Ala Pro Val Val Ser Gly Pro Ala Ala Arg Ala Thr 145 150 155 160 Pro Gln His Thr Val Ser Phe Thr Cys Glu Ser His Gly Phe Ser Pro 165 170 175 Arg Asp Ile Thr Leu Lys Trp Phe Lys Asn Gly Asn Glu Leu Ser Asp 180 185 190 Phe Gln Thr Asn Val Asp Pro Val Gly Glu Ser Val Ser Tyr Ser Ile 195 200 205 His Ser Thr Ala Lys Val Val Leu Thr Arg Glu Asp Val His Ser Gln 210 215 220 Val Ile Cys Glu Val Ala His Val Thr Leu Gln Gly Asp Pro Leu Arg 225 230 235 240 Gly Thr Ala Asn Leu Ser Glu Thr Ile Arg Val Pro Pro Thr Leu Glu 245 250 255 Val Thr Gln Gln Pro Val Arg Ala Glu Asn Gln Val Asn Val Thr Cys 260 265 270 Gln Val Arg Lys Phe Tyr Pro Gln Arg Leu Gln Leu Thr Trp Leu Glu 275 280 285 Asn Gly Asn Val Ser Arg Thr Glu Thr Ala Ser Thr Val Thr Glu Asn 290 295 300 Lys Asp Gly Thr Tyr Asn Trp Met Ser Trp Leu Leu Val Asn Val Ser 305 310 315 320 Ala His Arg Asp Asp Val Lys Leu Thr Cys Gln Val Glu His Asp Gly 325 330 335 Gln Pro Ala Val Ser Lys Ser His Asp Leu Lys Val Ser Ala His Pro 340 345 350 Lys Glu Gln Gly Ser Asn Thr Ala Ala Glu Asn Thr Gly Ser Asn Glu 355 360 365 Arg Asn Ile Tyr Ile Val Val Gly Val Val Cys Thr Leu Leu Val Ala 370 375 380 Leu Leu Met Ala Ala Leu Tyr Leu Val Arg Ile Arg Gln Lys Lys Ala 385 390 395 400 Gln Gly Ser Thr Ser Ser Thr Arg Leu His Glu Pro Glu Lys Asn Ala 405 410 415 Arg Glu Ile Thr Gln Asp Thr Asn Asp Ile Thr Tyr Ala Asp Leu Asn 420 425 430 Leu Pro Lys Gly Lys Lys Pro Ala Pro Gln Ala Ala Glu Pro Asn Asn 435 440 445 His Thr Glu Tyr Ala Ser Ile Gln Thr Ser Pro Gln Pro Ala Ser Glu 450 455 460 Asp Thr Leu Thr Tyr Ala Asp Leu Asp Met Val His Leu Asn Arg Thr 465 470 475 480 Pro Lys Gln Pro Ala Pro Lys Pro Glu Pro Ser Phe Ser Glu Tyr Ala 485 490 495 Ser Val Gln Val Pro Arg Lys 500 7 512 PRT Mus sp. 7 Met Glu Pro Ala Gly Ala Pro Gly Arg Leu Gly Pro Leu Leu Leu Cys 1 5 10 15 Leu Leu Leu Ser Ala Ser Cys Phe Cys Thr Gly Val Thr Gly Lys Glu 20 25 30 Leu Lys Val Thr Gln Pro Glu Lys Ser Val Ser Val Ala Ala Gly Asp 35 40 45 Ser Thr Val Leu Asn Cys Thr Leu Thr Ser Leu Leu Pro Val Gly Pro 50 55 60 Ile Lys Trp Tyr Arg Gly Val Gly Lys Ala Gly Cys Leu Ile Tyr Ser 65 70 75 80 Phe Thr Gly Glu His Phe Pro Arg Val Thr Asn Val Ser Asp Ala Thr 85 90 95 Lys Arg Asn Asn Met Asp Phe Ser Ile Arg Ile Ser Asn Val Thr Pro 100 105 110 Glu Asp Ala Gly Thr Tyr Tyr Cys Val Lys Phe Gln Lys Gly Pro Ser 115 120 125 Glu Pro Asp Thr Glu Ile Gln Ser Gly Gly Gly Thr Glu Val Tyr Val 130 135 140 Leu Ala Lys Pro Ser Pro Pro Glu Asp Pro Pro Arg Arg Gln Gly His 145 150 155 160 Thr Asp Gln Lys Val Asn Phe Thr Cys Lys Ser His Gly Phe Ser Pro 165 170 175 Arg Asn Ile Thr Leu Lys Trp Phe Lys Asp Gly Gln Glu Leu His Pro 180 185 190 Leu Glu Thr Thr Val Asn Pro Ser Gly Lys Asn Val Ser Tyr Asn Ile 195 200 205 Ser Ser Thr Val Arg Val Val Leu Asn Ser Met Asp Val His Ser Lys 210 215 220 Val Ile Cys Glu Val Ala His Ile Thr Leu Asp Arg Ser Pro Leu Arg 225 230 235 240 Gly Ile Ala Asn Leu Ser Asn Phe Ile Arg Val Ser Pro Thr Val Lys 245 250 255 Val Thr Gln Gln Ser Pro Thr Ser Met Asn Gln Val Asn Leu Thr Cys 260 265 270 Arg Asp Glu Arg Phe Tyr Pro Glu Asp Leu Gln Leu Ile Trp Leu Glu 275 280 285 Asn Gly Asn Val Ser Arg Asn Asp Thr Pro Lys Asn Leu Thr Lys Asn 290 295 300 Thr Asp Gly Thr Tyr Asn Tyr Thr Ser Leu Phe Leu Val Asn Ser Ser 305 310 315 320 Ala His Arg Glu Asp Val Val Phe Thr Cys Gln Val Lys His Asp Gln 325 330 335 Gln Pro Ala Ile Thr Arg Asn His Thr Val Leu Gly Leu Ala His Ser 340 345 350 Ser Asp Gln Gly Ser Met Gln Thr Phe Pro Gly Asn Asn Ala Thr His 355 360 365 Asn Trp Asn Val Phe Ile Gly Val Gly Val Ala Cys Ala Leu Leu Val 370 375 380 Val Leu Leu Met Ala Ala Leu Tyr Leu Leu Arg Ile Lys Gln Lys Lys 385 390 395 400 Ala Lys Gly Ser Thr Ser Ser Thr Arg Leu His Glu Pro Glu Lys Asn 405 410 415 Ala Arg Glu Ile Thr Gln Val Gln Ser Leu Ile Gln Asp Thr Asn Asp 420 425 430 Ile Asn Asp Ile Thr Tyr Ala Asp Leu Asn Leu Pro Lys Arg Arg Lys 435 440 445 Pro Ala Pro Gly Ser Leu Glu Phe Leu Asn Asn His Thr Glu Tyr Ala 450 455 460 Ser Ile Glu Thr Gly Lys Val Pro Arg Pro Glu Asp Thr Leu Thr Tyr 465 470 475 480 Ala Asp Leu Asp Met Val His Leu Ser Arg Ala Gln Pro Ala Pro Lys 485 490 495 Pro Glu Pro Ser Phe Ser Glu Tyr Ala Ser Val Gln Val Gln Arg Lys 500 505 510 8 391 PRT Mus sp. 8 Met Leu Leu Leu Asp Ala Trp Thr His Ile Pro His Cys Val Leu Leu 1 5 10 15 Leu Ile Leu Leu Leu Gly Leu Lys Gly Ala Ala Met Arg Glu Leu Lys 20 25 30 Val Ile Gln Pro Val Lys Ser Phe Phe Val Gly Ala Gly Gly Ser Ala 35 40 45 Thr Leu Asn Cys Thr Val Thr Ser Leu Leu Pro Val Gly Pro Met Arg 50 55 60 Trp Tyr Arg Gly Ile Gly Gln Ser Arg Leu Leu Ile Tyr Ser Phe Thr 65 70 75 80 Gly Glu Gly Phe Pro Arg Ile Thr Asn Thr Ser Asp Thr Thr Lys Arg 85 90 95 Asn Asn Met Asp Phe Ser Ile Arg Ile Ser Asn Val Thr Pro Ala Asp 100 105 110 Ser Gly Thr Tyr Tyr Cys Val Lys Phe Gln Arg Gly Pro Ser Asp Phe 115 120 125 Tyr Thr Glu Ile Gln Ser Gly Gly Gly Thr Glu Leu Ser Val Leu Ala 130 135 140 Lys Pro Ser Ser Pro Met Val Ser Gly Pro Ala Ala Arg Ala Val Pro 145 150 155 160 Gln Gln Thr Val Thr Phe Thr Cys Arg Ser His Gly Phe Phe Pro Arg 165 170 175 Asn Leu Thr Leu Lys Trp Phe Lys Asn Gly Asp Glu Ile Ser His Leu 180 185 190 Glu Thr Ser Val Glu Pro Glu Glu Thr Ser Val Ser Tyr Arg Val Ser 195 200 205 Ser Thr Val Gln Val Val Leu Glu Pro Arg Asp Val Arg Ser Gln Ile 210 215 220 Ile Cys Glu Val Asp His Val Thr Leu Asp Arg Ala Pro Leu Arg Gly 225 230 235 240 Ile Ala His Ile Ser Glu Phe Ile Gln Val Pro Pro Thr Leu Glu Ile 245 250 255 Arg Gln Gln Pro Thr Met Val Trp Asn Val Ile Asn Val Thr Cys Gln 260 265 270 Ile Gln Lys Phe Tyr Pro Pro Ser Phe Gln Leu Thr Trp Leu Glu Asn 275 280 285 Gly Asn Ile Ser Arg Arg Glu Val Pro Phe Thr Leu Thr Val Asn Lys 290 295 300 Asp Gly Thr Tyr Asn Trp Ile Ser Cys Leu Leu Val Asn Ile Ser Ala 305 310 315 320 Leu Glu Glu Asn Met Val Val Thr Cys Gln Val Glu His Asp Gly Gln 325 330 335 Ala Glu Val Ile Glu Thr His Thr Val Val Val Thr Glu His Gln Arg 340 345 350 Val Lys Gly Thr Ala Thr Lys Ser Gly Glu Val Phe Thr Pro Pro Leu 355 360 365 Cys Leu Asn Val Asn Trp Ala Leu Phe Phe Met Tyr Lys Val Thr Phe 370 375 380 Leu Ile Ile Val Ala Leu Ser 385 390 9 13 PRT Rattus sp. 9 Pro Ile Tyr Ser Phe Ile Gly Gly Glu His Phe Pro Arg 1 5 10 10 9 PRT Rattus sp. 10 Ile Val Glu Pro Asp Thr Glu Ile Lys 1 5 11 6 PRT Rattus sp. 11 Tyr Gly Phe Ser Pro Arg 1 5 12 12 PRT Rattus sp. 12 Ile Lys Glu Val Ala His Val Asn Leu Glu Val Arg 1 5 10 13 8 PRT Rattus sp. 13 Val Ala Ala Gly Asp Ser Ala Thr 1 5 14 107 PRT Unknown Organism Description of Unknown Organism Mus sp. or Homosapiens 14 Asp Glu Leu Gln Val Ile Gln Pro Glu Lys Ser Val Ser Val Ala Ala 1 5 10 15 Gly Glu Ser Ala Thr Leu Arg Cys Ala Met Thr Ser Leu Ile Pro Val 20 25 30 Gly Pro Ile Met Trp Phe Arg Gly Ala Gly Ala Gly Arg Glu Leu Ile 35 40 45 Tyr Asn Gln Lys Glu Gly His Phe Pro Arg Val Thr Thr Val Ser Glu 50 55 60 Leu Thr Lys Arg Asn Asn Leu Asp Phe Ser Ile Ser Ile Ser Asn Ile 65 70 75 80 Thr Pro Ala Asp Ala Gly Thr Tyr Tyr Cys Val Lys Phe Arg Glu Gly 85 90 95 Ser Pro Asp Asp Val Glu Phe Lys Ser Gly Ala 100 105 15 107 PRT Unknown Organism Description of Unknown Organism Mus sp. or Homosapiens 15 Asp Glu Leu Gln Val Ile Gln Pro Glu Lys Ser Val Ser Val Ala Ala 1 5 10 15 Gly Glu Ser Ala Thr Leu Arg Cys Ala Met Thr Ser Leu Ile Pro Val 20 25 30 Gly Pro Ile Met Trp Phe Arg Gly Ala Gly Ala Gly Arg Glu Leu Ile 35 40 45 Tyr Asn Gln Lys Glu Gly His Phe Pro Arg Val Thr Thr Val Ser Glu 50 55 60 Leu Thr Lys Arg Asn Asn Leu Asp Phe Ser Ile Ser Ile Ser Asn Ile 65 70 75 80 Thr Pro Ala Asp Ala Gly Thr Tyr Tyr Cys Val Lys Phe Arg Lys Gly 85 90 95 Ser Pro Asp Asp Val Glu Phe Lys Ser Gly Ala 100 105 16 107 PRT Unknown Organism Description of Unknown Organism Mus sp. or Homosapiens 16 Glu Glu Leu Gln Val Ile Gln Pro Glu Lys Ser Val Leu Val Ala Ala 1 5 10 15 Gly Glu Thr Ala Thr Leu Arg Cys Thr Ala Thr Ser Leu Ile Pro Val 20 25 30 Gly Pro Ile Met Trp Phe Arg Gly Ala Gly Ala Gly Arg Glu Leu Ile 35 40 45 Tyr Asn Gln Lys Glu Gly His Phe Pro Arg Val Thr Thr Val Ser Asp 50 55 60 Leu Thr Lys Arg Asn Asn Met Asp Phe Ser Ile Arg Ile Gly Asn Ile 65 70 75 80 Thr Pro Ala Asp Ala Gly Thr Tyr Tyr Cys Val Lys Phe Arg Lys Gly 85 90 95 Ser Pro Asp Asp Val Glu Phe Lys Ser Gly Ala 100 105 17 107 PRT Unknown Organism Description of Unknown Organism Mus sp. or Homosapiens 17 Glu Glu Leu Gln Val Ile Gln Pro Asp Lys Ser Val Ser Val Ala Pro 1 5 10 15 Gly Glu Ser Ala Ile Leu His Cys Thr Val Thr Ser Leu Ile Pro Val 20 25 30 Gly Pro Ile Gln Trp Phe Arg Gly Ala Gly Pro Ala Arg Glu Leu Ile 35 40 45 Tyr Asn Gln Lys Glu Gly His Phe Pro Arg Val Thr Thr Val Ser Glu 50 55 60 Ser Thr Lys Arg Glu Asn Met Asn Phe Ser Ile Ser Ile Ser Asn Ile 65 70 75 80 Thr Pro Ala Asp Ala Gly Thr Tyr Tyr Cys Val Lys Phe Arg Lys Gly 85 90 95 Ser Pro Asp Asp Val Glu Phe Lys Ser Gly Ala 100 105 18 107 PRT Unknown Organism Description of Unknown Organism Mus sp. or Homosapiens 18 Asp Glu Leu Gln Val Ile Gln Pro Asp Lys Ser Val Ser Val Ala Ala 1 5 10 15 Gly Glu Ser Ala Thr Leu Arg Cys Ala Met Thr Ser Leu Ile Pro Val 20 25 30 Gly Pro Ile Met Trp Phe Arg Gly Ala Gly Ala Gly Arg Glu Leu Ile 35 40 45 Ser Asn Gln Lys Glu Gly His Phe Pro Arg Val Thr Thr Val Ser Glu 50 55 60 Ser Thr Lys Arg Glu Asn Met Asp Phe Ser Ile Ser Ile Ser Asn Ile 65 70 75 80 Thr Pro Ala Asp Ala Gly Thr Tyr Tyr Cys Val Lys Phe Arg Lys Gly 85 90 95 Ser Pro Asp Asp Val Glu Phe Lys Ser Gly Ala 100 105 19 107 PRT Unknown Organism Description of Unknown Organism Mus sp. or Homosapiens 19 Asp Glu Leu Gln Val Ile Gln Pro Glu Lys Ser Val Ser Val Ala Pro 1 5 10 15 Gly Glu Ser Ala Thr Leu Arg Cys Ala Met Thr Ser Leu Ile Pro Val 20 25 30 Gly Pro Ile Met Trp Phe Arg Gly Ala Gly Ala Gly Arg Glu Leu Ile 35 40 45 Ser Asn Gln Lys Glu Gly His Phe Pro Arg Val Thr Thr Val Ser Glu 50 55 60 Leu Thr Lys Arg Asn Asn Leu Asp Phe Ser Ile Ser Ile Ser Asn Ile 65 70 75 80 Thr Pro Ala Asp Ala Gly Thr Tyr Tyr Cys Val Lys Phe Arg Lys Gly 85 90 95 Ser Pro Asp Asp Val Glu Phe Lys Ser Gly Ala 100 105 20 106 PRT Unknown Organism Description of Unknown Organism Mus sp. or Homosapiens 20 Glu Glu Leu Gln Val Ile Gln Pro Asp Lys Ser Val Ser Val Ala Pro 1 5 10 15 Gly Glu Ser Ala Ile Leu His Cys Thr Val Thr Ser Leu Ile Pro Val 20 25 30 Gly Pro Ile Gln Trp Phe Arg Gly Ala Gly Pro Ala Arg Glu Leu Ile 35 40 45 Tyr Asn Gln Lys Glu Gly His Phe Pro Arg Val Thr Thr Val Ser Asp 50 55 60 Leu Thr Lys Arg Asn Asn Leu Asp Phe Ser Ile Ser Ile Ser Asn Ile 65 70 75 80 Thr Pro Ala Asp Ala Gly Thr Tyr Tyr Cys Val Lys Phe Arg Lys Gly 85 90 95 Ser Pro Asp Val Glu Phe Lys Ser Gly Ala 100 105 21 106 PRT Unknown Organism Description of Unknown Organism Mus sp. or Homosapiens 21 Glu Glu Leu Gln Val Ile Gln Pro Asp Lys Ser Val Ser Val Ala Pro 1 5 10 15 Gly Glu Ser Ala Ile Leu His Cys Thr Val Thr Ser Leu Ile Pro Val 20 25 30 Gly Pro Ile Gln Trp Phe Arg Gly Ala Gly Pro Ala Arg Glu Leu Ile 35 40 45 Tyr Asn Gln Lys Glu Gly His Phe Pro Arg Val Thr Thr Val Ser Glu 50 55 60 Ser Thr Lys Arg Glu Asn Leu Asp Phe Ser Ile Ser Ile Ser Asn Ile 65 70 75 80 Thr Pro Ala Asp Ala Gly Thr Tyr Tyr Cys Val Lys Phe Arg Lys Gly 85 90 95 Ser Pro Asp Val Glu Phe Lys Ser Gly Ala 100 105 22 107 PRT Unknown Organism Description of Unknown Organism Mus sp. or Homosapiens 22 Asp Glu Leu Gln Val Ile Gln Ser Glu Lys Ser Val Ser Val Ala Ala 1 5 10 15 Gly Glu Ser Ala Ala Leu His Cys Ala Met Thr Ser Leu Ile Pro Val 20 25 30 Gly Pro Ile Met Trp Phe Arg Gly Ala Gly Ala Gly Arg Glu Leu Ile 35 40 45 Tyr Asn Gln Lys Glu Gly His Phe Pro Arg Val Thr Thr Val Ser Glu 50 55 60 Leu Thr Lys Arg Asn Asn Leu Asp Phe Ser Ile Ser Ile Ser Asn Ile 65 70 75 80 Thr Pro Ala Asp Ala Gly Thr Tyr Tyr Cys Val Lys Phe Arg Lys Gly 85 90 95 Ser Pro Asp Asp Val Glu Phe Lys Ser Gly Ala 100 105 23 107 PRT Unknown Organism Description of Unknown Organism Mus sp. or Homosapiens 23 Asp Glu Leu Gln Val Ile Gln Pro Glu Lys Ser Val Ser Val Ala Ala 1 5 10 15 Gly Glu Ser Ala Thr Leu Arg Cys Ala Met Thr Ser Leu Ile Pro Val 20 25 30 Gly Pro Ile Met Trp Phe Arg Gly Ala Gly Ala Gly Arg Glu Leu Ile 35 40 45 Tyr Asn Gln Lys Glu Gly His Phe Pro Arg Val Thr Thr Val Ser Glu 50 55 60 Leu Thr Lys Arg Asn Asn Leu Asp Phe Ser Ile Arg Ile Ser Asn Ile 65 70 75 80 Thr Pro Ala Asp Ala Gly Thr Tyr Tyr Cys Val Lys Phe Arg Lys Gly 85 90 95 Ser Pro Asp Asp Val Glu Phe Lys Ser Gly Ala 100 105 24 107 PRT Unknown Organism Description of Unknown Organism Mus sp. or Homosapiens 24 Asp Glu Leu Gln Val Ile Gln Pro Glu Ala Phe Val Ser Val Ala Ala 1 5 10 15 Gly Glu Met Ala Thr Leu Asn Cys Thr Val Thr Ser Leu Leu Pro Val 20 25 30 Gly Pro Ile Gln Trp Phe Arg Gly Ala Cys Pro Gly Gln Lys Leu Ile 35 40 45 Tyr Ser Pro Lys Arg Cys His Ser Pro Arg Val Thr Thr Ile Ser Asp 50 55 60 Gln Arg Lys Arg Asn Ser Thr Asp Tyr Ser Ile Arg Ile Ser Ser Ile 65 70 75 80 Thr Leu Glu Asp Ala Gly Thr Tyr Tyr Cys Met Lys Leu Arg Arg Ala 85 90 95 Ile Pro Ala Asn Val Glu Ile Lys Ser Gly Thr 100 105 25 107 PRT Unknown Organism Description of Unknown Organism Mus sp. or Homosapiens 25 Glu Glu Leu Gln Met Ile Gln Pro Glu Lys Leu Leu Leu Val Thr Val 1 5 10 15 Gly Lys Thr Ala Thr Leu His Cys Thr Val Thr Ser Leu Leu Pro Val 20 25 30 Gly Pro Val Leu Trp Phe Arg Gly Val Gly Pro Gly Arg Glu Leu Ile 35 40 45 Tyr Asn Gln Lys Glu Gly His Phe Pro Arg Val Thr Arg Val Ser Asp 50 55 60 Leu Thr Lys Arg Asn Asn Met Asp Phe Ser Ile Arg Ile Ser Ser Ile 65 70 75 80 Thr Pro Ala Val Val Gly Thr Tyr Tyr Cys Val Lys Phe Arg Lys Gly 85 90 95 Ser Pro Glu Asn Val Glu Phe Lys Ser Gly Pro 100 105 26 106 PRT Unknown Organism Description of Unknown Organism Mus sp. or Homosapiens 26 Glu Glu Leu Gln Val Ile Gln Pro Glu Lys Ser Val Ser Val Ala Ala 1 5 10 15 Gly Glu Ser Ala Ala Leu Gln Cys Thr Val Thr Ser Leu Asn Pro Val 20 25 30 Gly Pro Ile Gln Arg Phe Arg Gly Ala Gly Pro Gly Arg Lys Leu Ile 35 40 45 Tyr His Gln Lys Glu Gly His Phe Pro Arg Val Thr Thr Val Ser Asp 50 55 60 Leu Thr Lys Arg Thr Asn Met Asp Phe Ser Ile Cys Ile Ser Asn Ile 65 70 75 80 Thr Pro Ala Asp Ala Gly Thr Tyr Tyr Cys Val Lys Phe Gln Lys Gly 85 90 95 Ser Pro Asp Val Glu Leu Lys Ser Gly Ala 100 105 

What is claimed is:
 1. An isolated, purified, or enriched nucleic acid encoding a SIRP polypeptide.
 2. The nucleic acid of claim 1, wherein said SIRP polypeptide is a mammalian SIRP polypeptide.
 3. The nucleic acid of claim 2, wherein said mammalian SIRP polypeptide is a human SIRP polypeptide.
 4. A nucleic acid probe for the detection of nucleic acid encoding a SIRP polypeptide in a sample.
 5. Recombinant nucleic acid encoding a SIRP polypeptide and a vector or a promoter effective to initiate transcription in a host cell.
 6. An isolated, purified, recombinant, or enriched SIRP polypeptide.
 7. The SIRP polypeptide of claim 5, wherein said SIRP polypeptide is a mammalian SIRP polypeptide.
 8. The SIRP polypeptide of claim 6, wherein said SIRP polypeptide is a human SIRP polypeptide.
 9. A purified antibody having specific binding affinity to a SIRP polypeptide.
 10. A hybridoma which produces an antibody having specific binding affinity to a SIRP polypeptide.
 11. A method of detecting a compound capable of binding to a SIRP polypeptide comprising the steps of incubating said compound with said SIRP polypeptide and detecting the presence of said compound bound to said SIRP polypeptide.
 12. A method of screening potential agents useful for treatment of a disease or condition characterized by an abnormality in a signal transduction pathway, wherein said signal transduction pathway includes an interaction between a SIRP polypeptide and a natural binding partner, comprising the step of assaying said potential agents for those able to promote or disrupt said interaction as an indication of a useful said agent.
 13. A method for diagnosis of a disease or condition characterized by an abnormality in a signal transduction pathway, wherein said signal transduction pathway includes an interaction between a SIRP polypeptide and a natural binding partner, comprising the step of detecting the level of said interaction as an indication of said disease or condition.
 14. A method for treatment of an organism having a disease or condition characterized by an abnormality in a signal transduction pathway, wherein said signal transduction pathway includes an interaction between a SIRP polypeptide and a natural binding partner comprising the step of promoting or disrupting said interaction.
 15. An isolated nucleic acid molecule comprising a nucleotide sequence that; (a) encodes a polypeptide having the full length amino acid sequence set forth in SEQ ID NO.: 5, SEQ ID NO: 6, SEQ ID NO: 7, or SEQ ID NO: 8; (b) the complement of the nucleotide sequence of (a) or; (c) hybridizes under highly stringent conditions to the nucleotide sequence of (a) and encodes a naturally occurring SIRP protein.
 16. A nucleic acid molecule comprising a nucleotide sequence that encodes (a) a SIRP protein having the full length amino acid sequence of sequence set forth in SEQ ID NO.: 5, SEQ ID NO: 6, SEQ ID NO: 7, or SEQ ID NO: 8 except that it lacks one of the following segments of amino acid residues: extracellular domain, transmembrane domain, cytoplasmic domain, tyrosine bearing SH2 binding region in the cytoplasmic domain; or (b) the complement of the nucleotide sequence of (a).
 17. An isolated nucleic acid molecule comprising a nucleotide sequence that encodes a polypeptide having the full length amino acid sequence set forth in SEQ ID NO: 5; SEQ ID NO: 6, SEQ ID NO: 7, or SEQ ID NO: 8 except that it lacks at least one, but not more than two, of the domains selected from the group consisting of the extracellular domain, the transmembrane domain, and the SHP-2 binding domain.
 18. A recombinant vector containing the nucleotide sequence of any one of claims 14-17.
 19. A genetically engineered host cell containing the nucleotide sequence of any one of claims 14-18. 